Usage of nitrous in labour should be
banned.
“Nitrous Oxide in Labour: The Unexamined Use of a Schedule 6
Poison on a Defenceless Foetus During Peak Neurodevelopmental Vulnerability”
Say NO to Nitrous Oxide
Vitamin B12 loading of the brain happens predominantly in the womb, with little
more vitamin B12 loading of the brain for the rest of life
Vitamin B12 loading of the brain increases progressively as the foetus matures.
Vitamin B12 deficiency in the neonate is associated with delayed physical and
mental development.
Use of Nitrous Oxide during pregnancy can result in the formation of toxic,
and inactive NO-Co(III)Cobalamin
Reaction of Nitrous oxide with vitamin B12 is more likely in those who are
functionally B12 deficient
The effect of Nitrous oxide is higher in children with MTHFR +/+ or MTRR +/+
polymorphisms
Serum levels of vitamin B12 can be normal or elevated - Paradoxical B12
deficiency
Children with Paradoxical B12 deficiency due to Nitrous intoxication, will not respond to
MethylCo(III)B12 even if there is new synthesis of methionine synthase. Mounting evidence suggests that depending upon dose, mothers can also be
affected by Nitrous Oxide.
Data
suggests that even after years of supplementation with Adenosylcobalamin and
methylcobalamin that it is almost impossible to displace NO-Co(III)-Cbl.
Nitrous oxide permanently inactivates methionine synthase in a dose and time
dependent fashion. Vitamin B12 in the
body is distributed in two major pools, (i) the intracephalic area and the (ii)
extracephalic area. The intracephalic area (the brain) is loaded in utero and
once a baby is born there is almost no exchange of vitamin B12 into or out of
the cephalic area. Hence, damage by agents such as Nitrous oxide, leads to
permanent and irreversible damage of the brain, which lasts a life time,
effectively making a :"dead pool" of B12..
Nitrous Oxide and Birth of the birth of the Child
Pain control during labour, and the birth of the child can be controlled by the
use of Nitrous oxide and can be either given ad lib or via the control of an
anesthetist. The use of nitrous oxide during labour has increased from 1% of
births in 1980 to up to 50% in 2025.Nitrous oxide, Nitrous oxide has three
well‑established psychoactive properties, (i) it alters consciousness and
perception,(ii) It produces dissociation, euphoria, and anxiolysis, and (iii) It
impairs judgement, coordination, and memory formation. These properties are used
to alter the pain threshold of the mother, who is informed that it is "safe and
will not harm her unborn child". Nitrous oxide, though, also has another,
non-reversible activity, it permanently inactivates one of the most crucial
enzymes in the body, methionine synthase. As such it is one of the three causes
of vitamin B12 deficiency mediated, developmental delay.
The concept that autism, or developmental delay can be assessed at birth by the
anaesthetist is fanciful at best. Hence, neonatal development ex utero starts
once the baby is born, hence it would be impossible to gauge whether the child
has been affected by nitrous oxide or not, as there would be no development that
would be assessable in the first hour, day or even week after birth. In
addition, the assessment of autism, is a behavioural assessment carried out by a
trained psychiatrist (under the GSM-5 criteria), and would definitely fall
outside the remit, or experience of an anaesthetist.
The concept that the foetus would not be affected by nitrous is equally as
fanciful and is based on the illogical assumption that nitrous oxide can in some
way ONLY affect the NMDA receptors of the mother, and in no way affect the
interaction of nitrous oxide with Co(I)B12 within methionine synthase, and
thereby not affect methionine synthase activity of the foetus. In addition, the
effect on the foetus is not only likely to be more than that on the mother, it
most assuredly would be. Hence, the duality of nitrous oxide activity would mean
that as the mother is receiving pain relief and euphoria from the reaction of
nitrous oxide with the NMDA receptor, the foetal methionine synthase would, in a
time and dose dependent fashion, be progressively inactivated with every breath
of nitrous oxide that the mother takes. In addition, that whilst the nitrous
oxide can be expelled rapidly by the lungs of the mother, no such process occurs
in the foetus, rather, the accumulated nitrous oxide in the foetus would act as
a delayed release depot for transplacentally acquired nitrous oxide, resulting
from the mother’s repeated inhalation. .
It is not scientifically defensible to infer
long‑term neurodevelopmental safety of fetal nitrous oxide exposure from normal
neonatal appearance or short‑term postnatal observations. Autism, developmental
delay, and other neurodevelopmental conditions are behavioural diagnoses
made months to years after birth using structured criteria and specialist
assessment. They cannot be identified in the first hour, day, or even week of
life, and their assessment lies entirely outside the remit and expertise of the
anaesthetist.
Consequently, reassurance based on a normal neonatal
examination provides no meaningful evidence regarding the
absence of long‑term neurodevelopmental effects of nitrous oxide exposure in
utero.
Equally problematic is the implicit
assumption—sometimes stated, sometimes simply presumed—that nitrous oxide can
act selectively on maternal NMDA receptors without materially affecting the
fetus. This assumption is not supported by basic physiology or biochemistry.
Nitrous oxide is a small, inert gas that crosses the placenta freely. The same
molecule that produces maternal analgesia and euphoria via NMDA receptor
antagonism is also known to irreversibly inactivate methionine synthase
by oxidising the Co(I) form of methylcobalamin, and forming NO-Co(III)B12, which
totally inactivates methionine synthase..
Fetal methionine synthase activity is lower
at baseline and more vulnerable to inhibition than
maternal enzyme at the same exposure. Thus, while the mother experiences
transient, reversible analgesia as her brain nitrous oxide concentration rises
and falls with each inhalation, the foetus is subjected to a cumulative,
time‑dependent inactivation of methionine synthase throughout the
exposure period.
Although nitrous oxide is rapidly eliminated via the
maternal lungs once administration ceases, the fetus has no independent
route of excretion. Fetal elimination depends entirely on placental
transfer back into the maternal circulation. During ongoing maternal use, this
results in a state of continuous fetal exposure, even as
maternal brain concentrations fluctuate in a wave‑like pattern.
Taken together, these considerations make it
untenable to claim that the fetus is unaffected by nitrous oxide, or that normal
short‑term neonatal observations can be taken as evidence of long‑term
neurodevelopmental safety. Any assertion to the contrary rests on assumptions
that are physiologically implausible and inconsistent with established
biochemical mechanisms."
The problem with nitrous oxide though is that it is toxic to the foetus,
1. The foetus is exposed to a
psychoactive agent without benefit The mother receives analgesia and
altered perception. The foetus receives only biochemical disruption, and the
inevitable and continuing inactivation of methionine synthase..
2. The foetus is exposed at a
time when psychoactive effects are maximally harmful. During late gestation, the brain is
undergoing: (i) neuronal migration, (ii) dendritic arborisation, (iii) synaptic wiring
(iv) methylation‑dependent gene regulation
A psychoactive agent that alters
neurotransmission or methylation at this stage is not benign.
3. The Schedule 6 classification
implicitly recognizes nitrous as both toxic and psychoactive, The warnings required on consumer
products explicitly reference: (i) inhalation risks, (ii) neurological effects,
(iii) altered mental state (iv) harm to minors
Yet obstetric practice exposes
the foetus — a minor — to the same substance that is both toxic and psychoactive
at 50% concentration to an adult.
Nitrous oxide has never been
properly evaluated for use in pregnancy. Its current use is a historical
artefact, not an evidence‑based practice. The Schedule 6 classification now
makes this regulatory gap untenable
Do not for one minute believe that the anaesthetic
profession has the mother and baby's best interests at heart. If they did they
would advise against any use of nitrous oxide.
Methionine synthase binds to
MethylCo(III)B12 which subsequently acts as
a Methyl Donor to convert Homocysteine to Methionine, and the resultant
Co(I)B12 can act as an acceptor for incoming
methyl groups such as those on 5-methyltetrahydrofolate.
MethylCo(III)B12 + Homocysteine [Methionine Synthase] <=>
Co(I)B12 + Methionine
Co(I)B12 + 5MTHF [Methionine Synthase] <=>
MethylCo(III)B12 + THF During the methylation reaction of
Co(I)B12 + Nitrous Oxide <=>
NO-Co(III)B12
Normally, in the absence of incoming folate, Co(I)B12 is reduced to Co(II)B12
and MethylCo(III)B12 is formed by the action of MTRR and SAM. If this does not
occur, methionine synthase releases Co(II)B12 and thereby frees up the binding
site for MethylCo(III)B12. The Co(II)B12 then is secreted into serum and so
contributes to the elevated serum B12 levels. Unless functional B12 markers,
such as MMA and homocysteine are measured it is not possible to tell if the
vitamin B12 is functionally active or inactive. Hence
Paradoxical B12 deficiency
will result. Thus, poisoning with nitrous oxide is very different to functional
B12 deficiency due to folate, or functional B2 deficiency, in that whilst
Co(II)B12 or Co(I)B12 can be converted to MethylCo(III)B12, thereby restoring
activity of the [MethylCo(III)B12-methionine synthase] complex, NO-Co(III)B12
cannot be displaced and thereby regenerate the activity of the enzyme. Higher levels of
Co(I)B12
are present in
functional B2
deficiency, such as occurs in Iodine, Selenium and/or Molybdenum deficiency, due to lack of activity of
the FAD/NADH-dependent MTHFR enzyme, particularly in those with mutations
in the MTHFR protein, or in those with a diet low in folate, thereby making those individuals more susceptible to the action of
nitrous oxide. The inactive
NO-Co(III)B12
would be indistinguishable from
inactive Co(II)B12, and when measured in the
current total serum B12 and the inappropriately named active B12 tests, as they
do not distinguish which analogue of cobalamin is being measured, cyanocobalamin, hydroxycobalamin, methylcobalamin, adenosylcobalamin, Co(II)cobalamin,
Co(I)cobalamin, glutathionyl-Co(III)cobalamin or cysteinyl(III)cobalamin, to name
but a few.
An indication of the extent of damage that nitrous can do to the nervous system can be gleaned
from those who use Nangs, and their devastating neurological consequences.
Reports of side-effects include “subacute-onset, progressive distal lower limb
sensory symptoms and unsteadiness”, “subacute combined degeneration of the
cord”” ataxia and progressive paresis”, depression, development of diseases of
the brain, spine and nerves. The severity of these reactions has led the UK
government to consider criminalizing the use of Nitrous Oxide. Curiously, this
suggest has not been carried through and currently nitrous oxide is used over
70% of births in the UK Genetically,
Nitrous oxide sensitivity should be higher in those with MTRR +/+ mutations, as
is found for the following SNPs, MTRRG12099A, MTRRA66G, and in MTHFR mutations
A1298C, and rs13306571..
N2O irreversibly inactivates methionine synthase in everyone
Nitrous
oxide was commonly used as an anaesthetic gas, yet as long ago as 1956 (Lassen
et al, 1956) it was realized that the activity of vitamin B12 was destroyed
by nitrous oxide use and could cause megaloblastic anemia. In 1968, Banks and
co-workers demonstrated that nitrous oxide could react with the cobalt in
vitamin B12 and lead to the inactive NO-Co(III)B12 complex. The destruction of the
activity of vitamin B12 is dependent upon the time and dose of administration of
nitrous, with over 50% of individuals producing signs of megaloblastic
depression of bone marrow function (Nunn and Chanarin, 1978). As early as 1978
(Amess et al, 1987) the use of nitrous oxide for anaesthesia was found to be
contra-indicated, yet to this day it is still used, and many individuals report
signs of B12 deficiency following use. Unbelievably, despite numerous
publications showing poor outcomes of nitrous oxide use in pregnancy, and
several demonstrating an association between nitrous and autism, and over 200
publications, demonstrating inactivation of vitamin B12 with subsequent
sequelae, clinicians in the US, UK and Australia claim "“ Initiation
and management of nitrous oxide by registered nurses is a safe and
cost-effective option for labor pain.”.
In the UK, up to 77% of patients use inhaled nitrous for labour analgesia(See PDF). One of the problems with Nitrous
inactivation of vitamin B12 activity is that the levels of B12 in serum still
remain high, yet paradoxically the B12 is inactive - as per the discussion on
paradoxical vitamin B12 deficiency. Unbelievably, nitrous oxide is still used as
an anaesthetic to this day in the USA ,UK and Australia, both on mothers during pregnancy, and
also on young children. Evidence suggests that this alone is responsible for
many cases of autism (Xin et al, 2024).
It has been known for over 40 years that the use of nitrous oxide in anaesthesia
(laughing gas) or in recreational abuse, can cause vitamin B12 deficiency (Shah
and Murphy, 2019: Tani etal, 2019; Oussalah etal, 2019; Chi, 2018; Stockton etal,
2017; Massey etal, 2016: Garakani etal, 2014; Safari etal, 2013; Chiang etal,
2013; Krajewski etal, 2007; Cohen etal, 2007; Jameson etal, 1999; Smith, 2001:
Deleu etal, 2001; Mayall, 1999; Horne and Holloway, 1997: Kinsella and Green
1995; Carmel etal, 1993; Koblin etal,1990; O'Leary etal, 1985; van der Westhuyzen and Metz, 1984; 1982; Lumb etal, 1982; Kondo etal, 1981: Seteinberg
etal, 1981; McKenna etal, 1980; Linnell etal, 1978; Deacon etal, 1978). Post
surgical complications of the use of Nitrous include peripheral neuropathy (Neuveu
etal, 2019: Egan, 2018: Kaski etal, 2017; Richardson 2010), metabolic
encephalopathy (Vive etal, 2019), myeloneuropathy (Edigin etal, 2019;
Friedlander and Davies, 2018; Alt etal, 2011; Waklawik etal, 2003; Sesso etal,
1999: Nestor and Stark, 1996), neuropathy (Gullestrup etal, 2019; Conaerts etal,
2017:Middleton and Roffers, 2018), pancytopenia (Norris and Mallia, 2019),
Myopathy (Williamson etal, 2019), myelopathy (Dong etal, 2019; Mancke etal,
2016; Probasco etal, 2011: Hathout and El-Saden, 2011; Pema et al, 1998),
severe neuropsychiatric symptoms (Lundin etal, 2019), combined degeneration of
the spinal chord (Lan etal, 2019; Patel etal, 2018; Anderson etal, 2018;
Antonucci, 2018; Keddie etal, 2018; El-sadawi etal, 2018; Yuan etal 2017:
Buizert etal, 2017; Chen and Huang, 2016; Pugliese etal, 2015: Chaugny etal,
2014; Cheng etal, 2013; Lin etal, 2011; Wijesekera, etal, 2009; Renaud etal,
2009: Wu etal, 2007; Ahn and Brown, 2005 Ilniczky etal, 2003: Beltramello etal,
1998: Rosener and DIchgans, 1996), neurotoxicity (Johnsonn etal, 2018),
neuronopathy (Morris etal, 2015), polyneuropathy (Alarcia etal, 1999),
psychosis (Sethi et, al, 2006), dementia (El Otmani etal, 2007), ataxia (Miller
etal, 2004), megaloblastic anemia (Barbosa etal, 2000), neurological impairment
(McNeeely etal, 2000), neurologic decompensation (Felmet etal, 2000), neurologic
degeneration (Flippo and Holder, 1993), spastic paraparesis (Lee etal, 1999).
Curiously, Nitrous is still recommended by the American Association of
Anesthesiologists, NSW Department of Health, and the Association of
Anesthesiologists, the New Zealand College of Midwives..
In
fact, several countries with high standards of healthcare, such as Canada,
Sweden, Australia, Finland, and the United Kingdom, use a blend of 50%
oxygen and 50% nitrous oxide to
treat pain during labour.
Whilst they do not express concerns about potential damage to the newborn, they
do, however, express concerns about the potential effect on Global warming, which
is of greater concern than the effect on the neonatal brain!!
The rational appears to be due to the replacement of epidural medication, with
its risk on the spine, with the nitrous oxide. This attitude typifies the
medical profession, treat the problem now, worry about the side effects later.
We have contacted numerous hospitals, the Royal Children's Hospital Melbourne,
Mayo Clinic Kopabirth, NZ College of Midwives, midwife associations, The America
Pregnancy Association, Queensland Government, The Royal Australian and New
Zealand College of Gynecology ("Excellence in women's health"), Doctors for the Environment and
anaesthesiologists expressing our concerns yet not one has "returned our call".
Atrocious!!
Interestingly, the increase in the use of Nitrous from around 1% of births in
1980, in 2011-2014 when it is was 12% to 35=55% of births in 2024, has paralleled the rise in the rate of
autism from <0.1% to now ~ 3%. In response to concerns about health, Dr Vitoria Eley of Queensland Department of Health "Great to see you engaging with
the anaesthesia literature"..Queensland Government "Nitrous Oxide : Gas is safe
for your baby..." Estimates suggest that if a woman chooses nitrous oxide,
she has an 8-10% chance of having a baby who subsequently is diagnosed with
autism, and a 25% chance of the child having ADHD or OCD. Use of Nitrous is so
frequent that hospitals are using scrubbers to try to remove this greenhouse gas
(Khan-Perez et al, 2022). Despite the well known dangers of Nitrous,
institutions such as RANZCOG are still recommending the use of Nitrous to
pregnant women. The American College of Obstetricians and Gynecologists have
disregarded all the publications on the dangers and nitrous and have take the
view that have decided that since there are no studies on the use of Nitrous and
the neonate, that they will disregard the literature and instead of erring on
the side of caution have dispelled the possibility of harm (Home
| ACOG). "The
use of N2O
has increased in labor and delivery units across the United States since 2011.
Despite inferior analgesic properties compared to epidural analgesia, N2O
offers a safe alternative for many parturients who want a greater sense of
control and mobility. Broughton etal, 2020). What is worse is that for many
mothers, they receive information in baby classes, taught by nurses that claim
nitrous to be safe.
When one examines the age ranges for both ASD and for AD, it is clear that there
is some event that occurred, or some change that has occurred, since 1980, that
has started the dramatic increase in the rate of autism. All of the children
that we have data for who have ASD or ADHD, are functionally deficient in
vitamin B12, with normal to elevated serum vitamin B12, and standard markers
MMA, HVA, VMA, QA, KA, 5HIAA, pyroglutamic acid and phosphoric acid.
N2O inhibition of methionine synthase is rapid, potent,
and irreversible inactivation in all if exposed for long enough, and harmful in a substantial proportion of
patients that are not identified before exposure
A Schedule 6 Toxin in the Delivery Suite: Dose‑Dependent Methionine Synthase
Inactivation in the Near‑Term Foetal Brain
There are
several groups who have shown the deleterious effects of nitrous on the brain.
Thus Selzer (2003) demonstrated increased susceptibly of those with MTHFR
mutations to Nitrous Oxide, and
Kalikiri and co-workers (2004) found a dramatic change in MMA and homocysteine
levels in nitrous, as too Baum (2007).
The study findings of a mechanistic link between nitric oxide levels and autism
spectrum disorder are
significant (Jackson, 2023).
Prolonged misuse of nitrous oxide for recreational purposes can lead to spinal
cord demyelination and loss of the ability to walk, neurologists have warned.
Potential signs
of deficiency in folate, or functional B12 would be any orofacial defects such
as Cleft palate, tongue tie, difficulty feeding.
The extent of
damage to the brain will be dependent upon how long the child was exposed to
nitrous oxide, and at what stage their development was at. Hence areas of the
brain that were most active at the time of exposure are most likely to be
affected the most. At time of birth this would be cerebellum, followed after
birth by the subcortical areas and then the cerebral cortex.
Of note, Human foetal/neonatal and geriatric kinetics of inactivation and
reactivation are unknown in any tissue.
N2O is the only inhaled anesthetic that will kill
everyone who breathes it at clinical concentrations for 5-7 day
A Schedule 6 Toxin in the Delivery Suite: Direct Fetal Exposure via Maternal
Inhalation — the Only Available Biological Delivery Route
Identification
Developmental delay, due to nitrous oxide
intoxication is not detectable for months after the birth. Hence, statements,
such "As does not harm the baby" have little to no verification.
Whilst
there is a scintilla of evidence about brain damage with nitrous oxide it would
not be prudent to continue the practise, particularly since the association of
increased use of nitrous parallels the increased rate of autism.
Deleterious consequences of nitrous are long-lasting,
not “short acting”
Symptoms include Complete
Regression into autism, T
Nitrous oxide intoxication and the mother Evidence is
mounting that whilst the mother may not show signs of nitrous intoxication at
the time of birth, many show evidence of vitamin B12 deficiency later, with
serum levels of vitamin B12 being raised. In these individuals markers of methyl
B12 deficiency would be elevated homocysteine, as well as
HVA, VMA, QA, KA, 5HIAA, pyroglutamic acid and phosphoric acid. Whilst the
levels may be lower than in the child, the levels will persist and are unable to
be changed by repeated high dosages of vitamin B12. Further, there is evidence
that the inactive NO-Co(III)B12 may then be used to load the brain of subsequent
children, who will then show signs of B12 deficiency at birth, regardless of
whether nitrous oxide is delivered or not. Currently there have been no
successful examples of dislodging NO-Co(III)B12 from the mother, who may
subsequently suffer conditions such as Chronic Fatigue Syndrome, or early onset
dementia. Hence even single usage of nitrous oxide during labour may have long
lasting deleterious effects upon the mother and subsequent children. At this
time the medical profession has shown a "No Mia Culpa" attitude, denying all
knowledge of the risk of nitrous oxide and definitely not accepting any blame
for the damage it has caused. This is totally contra to the Hippocratic Oath and
its intension to "Do no harm". It is recommended that every mother who has had
nitrous oxide during labour be tested for functional B12 deficiency, and that
this be resolved before any attempt is made to have another child.
When Analgesia for the Mother Becomes Toxic Exposure for the Foetus: Rethinking
Nitrous Oxide as a Schedule 6 Poison in Labour
Treatment of Nitrous oxide intoxication
Treatment of
Nitrous oxide inhalation is possible if it is done early, however, treatment has
to be quick, or permanent damage is done. Successful treatment, though appears
to occur mainly in those who had an absolute B12 deficiency,. Hence if the body
normally has 300-350 pmol/ml transcobalamin-bound vitamin B12, but in deficiency
it has less than 200 pmol/ml, then administering excess vitamin B12 will cause a
reduced but functional sufficiency of vitamin B12. These people can be "rescued"
by the addition of high doses of vitamin B12, incoming B12 will still show a
response. However, in individuals with
a saturated transport system and a deficiency in functional B2, and particularly
in those with MTHFR and MTRR mutations, nitrous intoxication will affect all the B12, and
so addition of excess B12 will not be effective. This has been noted by various
workers, who have claimed some success in treatment of some of the individuals
who had nitrous, but not all (Brunt
et al, 2024; Boulin et al, 2025;
Einsiedler et al, 2022; Zheng et al, 2020; Xiang et al, 2021) This, though, is not what happens
following exposure during labour, and so the potential for treatment is lost,
particularly given that diagnosis of neurological damage is not done until many
months or even years later. There is hope though, but it depends upon making
sure that you get any deficiencies such as functional B2 and B12 deficiencies
right first, and then slowly let nature take its course. In those who are
severely affected this may take years!! Treatment should
ensure that any Iodine, Selenium and/or Molybdenum deficiency is resolved. This
is to ensure maximal activity of what little active methionine synthase enzyme
there still is. A constant supply of methylCo(III)B12 is required to try to load
the brain with as much methylCo(III)B12 as possible, so that any new methionine
synthase that is synthesized has the active from of B12 around during synthesis. To further optimize
the activity of residual methionine synthase, it is desirable to provide a
constant supply of 5MTHF. This, though, is not so straight forwards. If one was
to over-supplement with 5MTHF, the material will not be trapped within the cells
as trapping of folate within the cell requires polyglutamination, and in order
for that to occur, folate has to be within the folate cycle, and this can only
occur by providing folate (folic acid), as 5MTHF has to be processed by
methionine synthase before it is converted to Tetrahydrofolate, and given that
methionine synthase activity is extremely low in nitrous oxide affected
children, this method will be very inefficient. Further, supplying high dose
5MTHF will raise measured serum folate levels (of unknown identity), which is
diagnostic of functional methionine synthase deficiency, but which is poorly
understood by pathology labs and particularly by clinicians. Instead, it would
be better to supply folic acid, which enters the folate cycle and is quickly
converted to dihydrofolate, and then tetrahydrofolate, which is the normal
analogue of folate that cycles within the cell. The THF can then contribute to
various reactions within the folate cycle, it will be polyglutaminated and so
stay within the cycle, and will provide a ready supply of THF for conversion to
5,10-methylene-THF, which will be processed by MTHFR to keep supplying 5MTHF for
reaction with methionine synthase. The presence of the polyglutaminated "tail"
will ensure that the THF is always available for modification, rather than being
rapidly lost from the cell. Whilst folinic acid could potentially be used, it is
much more expensive and does not provide any advantage to the child and has
mainly been used as a folate derivative in persons being treated with
methotrexate.
Say NO to the use of Nitrous.
Markers of functional B12 deficiency due to
Markers of functional B12 deficiency would be very
similar to those observed with with functional B2/B12 deficiency, and would
include
Elevated or normal serum vitamin B12
Elevated MMA and homocysteine
Elevated neurotransmitter metabolites, HVA, VMA,
QA, KA, 5HIAA
Elevated pyroglutamic acid
Reduced SAM:SAH ratio
Reduced GSH:GSSG ratio
Low serum creatinine
The most distinguishing features of Nitrous oxide
toxicity is the
Lack of correlation between MMA and markers of
Methyl B12 deficiency.
The ratio between MMA and HVA is less than 0.4
MMA;HVA.
Inability to resolve the methyl B12 deficiency
markers by fixing the functional B2 markers.
Comparison of Methyl deficiency markers against MMA.
Neurotypical (left) vs ASD (right)
Comparison of MMA vs the methyl B12 deficiency markers HVA, VMA and QA in normal
individuals reveals a close linear correlation. In comparison there was little
correlation between HVA, VMA and QA and MMA in the ASD example. Data was
collected over a 4 year period of treatment with Adenosyl/Methyl B12. In that
period MMA levels decreased in both groups, and methyl deficiency markers
reduced in the control, however, there was no evidence of change of Methyl B12
deficiency markers in the ASD individual.
Comparison of HVA to MMA between Nitrous affected autism child (left panel) and B12 deficient neurotypical
individual (right panel) shows a considerable difference in the ratio of HVA:MMA.
Hence, in the NT individual, HVA generally has a close relationship to MMA, with
2:1 being the highest ratio, , but in the nitrous oxide exposed child, the ratio
of HVA:MMA varies considerable from 5:1 to 1.3: 1 with many data points >3:1. In
addition, despite MMA being less than 1.0, in the nitrous affected child HVA has
persisted above 3.0. In contrast the NT individual HVA was below 2.0 for most
oft he data, and reached 1.2.
The data is commensurate with what is known about nitrous poisoning in babies.
Hence, " babies affected by nitrous have a life long mental and often physical
disability, requiring constant care, and repetitive medical and educational
costs, often costing over $50,000 per year".
A Schedule 6 Poison in the Birth Room: The Fetus as the Involuntary End‑User of
Maternal Nitrous Oxide
Effect of Nitrous on the brain
Nitrous mainly affects areas of the brain involved in neurotransmission, sensory
processing and cognitive function. Exposure to nitrous during delivery affects
those areas under-rapid development and synaptic formation. Areas to be affected
would be the Frontal Cortex, which affects executive functioning and decision
making. Nitrous acts as an NMDA receptor antagonist and affects glutamatergic
signaling, affecting attention, impulse control and higher cognitive functions.
Nitrous affects dopaminergic functioning thereby causing movement disorders, and
difficulties in co-ordination. Nitrous also affects the cerebellum, potentially
affecting motor development and causing difficulties with balance. Nitrous also
has been linked to subacute spinal degeneration, thereby resulting in
neuropathy, weakness and altered reflexes.
Usage of nitrous in labour should be
totally banned.
When a Schedule 6 Toxin Reaches the Foetal Brain: Maternal Inhalation as the
Unintended Delivery Pathway
Thalidomide similarities
In many ways the
Nitrous "story" is similar to the Thalidomide story. Hence the drug was tested
on women who were not pregnant, and was found to be safe. However, when it was
administered as as a sedative and a treatment for morning sickness, with
disastrous consequences. Potentially, though Nitrous is worse. Hence many of the
thalidomide babies had limb deformities, they were otherwise OK. In contrast,
babies that are affected by nitrous have a life long mental and often physical
disability, requiring constant care, and repetitive medical and educational
costs, often costing over $50,000 per annum.
Prevention of Nitrous oxide intoxication
Obviously
prevention involves total avoidance of nitrous oxide during pregnancy. This
appears to be totally ignored by the medical profession. In Australia for
instance, 80% of women in labour receive pain relief of which 52% use nitrous
oxide. It is little wonder that the rates of autism and ADHD have sky-rocketed
in the past 30 years. See
Nitrous). Every mother that we have spoken to (9 at present), who had
nitrous and who subsequently had a child diagnosed with autism, was told that
nitrous oxide was safe. Further, and perhaps more worryingly, every web-site for
obstetric nurses and maternal health care has also said the same. we have
contacted many, and not one has replied. Comments from mothers include "however
after my very long use of nitrous in labour (6 hours of more), my son later
developed autism". "I had nitrous oxide as advised during my first birth.... My
child has ASD". "I had it with both kids. Was low in B12 when pregnant with my
second child (diagnosed ASD)". "I had nitrous oxide during labour with both my
children, both autistic". In what is arguably
one of the best examples of cognitive dissonance, the Anaesthetic Society of
Australia has Not only failed to acknowledge the plethora of references
describing the inactivation of the essential enzyme, methionine synthase by
nitrous oxide, as well as the categorization of nitrous oxide as a Schedule 6
toxin, and the more recent publications on the linkage of the use of nitrous
oxide to the subsequent development of autism in the babies born to mothers
treated with nitrous oxide during labour, and the recent death of a young child
by nitrous oxide intoxication, and the multitude of examples of degeneration of
the spine in recreational nitrous oxide users, rather it has failed to modify
its practise of using nitrous oxide by proclaiming that it will continue to use
nitrous oxide until a clinical trial demonstrates that it harms the foetus
during delivery.This "no mia culpa" attitude flies in the face of the
Hippocratic oath, and more specifically ignores two of the major tenets of the
oath (i) Non-maleficence, the avoidance of causing harm to patients, and (2)
Prohibition of certain acts, which forbids administering poison... Hence
administration of a Schedule 6 toxin to a minor (the foetus), subsequently
resulting in brain damage and developmental delay of the soon to be born child.
Treatment Treatment of
nitrous oxide intoxication should begin as soon as possible by injection of
large amounts of Methyl B12. If treatment is delayed, the RnB protocol
(https://b12oils.com/rnbautism.htm ) should be used to ensure correction of
functional B2 deficiency, and also high dose Adenosyl/Methyl B12, in the hope
that the toxic NO-Co(III)B12 can be displaced. The longer the nitrous exposure
and the longer the time until treatment is commenced, the less success there
will be. For this reason, Prevention is Better than cure. The problem with
treatment is that all forms of vitamin B12 in the body are bound up by B12
binding proteins, such as Haptocorrin, and Transcobalamin. The affinity (or
binding strength) of these proteins are so high, that it is almost impossible to
displace the bound vitamin B12 (of any analogue) with free vitamin B12. In
addition, it has not been possible to displace the NO-Co(III)B12 with free
MethylCo(III)B12. This effectively means that until the Methionine synthase is
degraded, there is no possibility of fixing the Methyl Co(III)B12 deficiency. In
addition, there is almost no transport of vitamin B12 into the brain, once the
child is born, thus making displacement almost impossible.
Usage of nitrous in labour should be
totally banned.
Further Comments. Nitrous oxide (N2O) primarily affects
brain regions involved in neurotransmission, sensory processing, and
cognitive function. If exposure occurs during delivery, the areas
most vulnerable would likely be those undergoing rapid development and
synaptic formation. Based on current research, the following brain regions
may be impacted: 1. Frontal Cortex (Executive
Function & Decision-Making) 2. Basal Ganglia (Motor Control &
Coordination) 3. Cerebellum (Balance & Motor
Learning) 4. Default Mode Network
(Self-Referential Thinking & Sensory Processing) 5. Spinal Cord (Peripheral Nervous
System & Reflexes) While these effects are hypothetical
in the context of neonatal exposure, further research is needed to determine
whether maternal NO use during labor has measurable impacts on newborn
neurodevelopment. nitrous oxide (N2O) exposure can
influence neuronal stem cell viability, but its effects depend on concentration
and duration of exposure. Research suggests that nitric oxide (NO), a
related molecule, plays a complex role in neural stem cell fate—sometimes
promoting proliferation and other times inhibiting neurogenesis. Effects of Nitrous Oxide on
Neuronal Stem Cells 1. Neurogenesis inhibition 2. Stem cell viability and
Proliferation 3. Potential implication for
nitrous oxide exposure The brain has a remarkable ability to recover
and adapt, but the extent of recovery after nitrous oxide exposure during
birth depends on several factors, including duration of
exposure, severity of B12 inactivation, and individual metabolic resilience. Potential for Recovery Neuroplasticity &
Repair Mechanisms: Vitamin B12
Restoration: Severity of Initial
Damage: Research Insights Some studies suggest that early
intervention can improve outcomes, but long-term effects of
neonatal nitrous oxide exposure remain an area of ongoing investigation. These studies aim to correct
functional B12 deficiency first before expecting significant neurological
recovery, particularly in children. Since B12 is essential for
methylation, DNA synthesis, and myelin formation, its absence or dysfunction
can severely impact brain development and repair processes. Why Fixing B12 Deficiency is
Crucial for Recovery If a child has experienced prenatal
or early-life nitrous oxide exposure, addressing B12 status as early
as possible could maximize their potential for recovery. Further: The partitioning of inhaled nitrous oxide (N2O) into fetal blood and brain compared to the mother's brain depends on several
factors, including placental transfer, fetal circulation, and tissue
solubility. In this regard, the brain of a neonate is around 12% total
weight of the child, whilst that of an adult is around 2%, hence the effect on
the neonate is likely to be 6 times higher than the mother. 1. Placental Transfer of N2O 2. Partitioning into Foetal Brain vs. Maternal Brain 3. Potential Effects on Fetal Brain Development
Comparison of Nangs to Nitrous Oxide gas. Usage of nitrous in labour should be
totally banned.
Comparison of Thalidomide to Nitrous Oxide gas.
Recommendations to cease use of Nitrous Oxide In recent years, there have been recommendations to eliminate
nitrous oxide from medical use due to its toxicity, possible increase in
morbidity and mortality, and adverse environmental effects. (Dimic et al,
2023) . Of these reasons, the most pressing appears to be that nitrous is the
fifth largest contributor to green-house gas emissions, rather than to damage
to the brain of a child (Natale et al, 2026). Since October 2022 in Australia, nitrous oxide has been
classified as a Schedule 6 poison, prohibited from supply to anyone under 16
due to its neurotoxic potential. Yet in obstetric practice, the same substance
is administered in 50% concentration to pregnant women, resulting in
involuntary foetal exposure at levels vastly exceeding occupational safety
limits. The foetus — a minor under 16, unable to consent, and receiving no
therapeutic benefit — is exposed to a Schedule 6 toxin at the moment of peak
neurodevelopmental vulnerability. This appears inconsistent with both the
intent and the letter of the Schedule 6 protections Further to this, the clinician or associated health care
worker, due to their actions in supplying a Schedule 6 poison to a person
under 16 would be legally liable for any damage that this incurs. Nitrous
oxide, No Laughing Matter. During labour, the delivery of Nitrous oxide, occurs
through an exquisitely maintained Pharmaceutical window with the mother
carefully ensuring that levels of nitrous never drop below the minimum
effective concentration of this Schedule 6 toxin. By comparison, the
Pharmaceutical Industry has yet to design such a perfect delivery system as
that of the mother receiving nitrous from her health professional. With every breath she takes, she ensures that she
continuously bathes the brain of her foetus in the highly toxic, Schedule 6
toxin, nitrous oxide (One should be aware that it is illegal to give a
Schedule 6 toxin to persons under the age of 16. Such a person would be the
foetus, within the mother’s womb). Her search for pain relief means that the
nitrous is continuously delivered at a concentration above the minimum toxic
range, in an optimal delivery device, the mother. Unknowingly, the mother
repeatedly breathes in a soothing gas containing 500,000 ppm of nitrous oxide,
a mixture that is 20,000 times the safe upper environmental exposure limit,
and delivers the nitrous, via the placenta to the soon to be delivered foetus. The brain of the foetus, though, is not the brain of the
mother. In contrast to the mother’s highly developed brain, for the foetal
brain, it is the start of its neurodevelopmental journey. During the 3rd
trimester of pregnancy, it is primed for its peak of differentiation and
synaptogenesis. With every breath of euphoria generating feeling of the
mother, more and more damage is being inflicted on the foetal brain, ensuring
that it becomes progressively less capable of developing normally and so
ensures that if its development does proceed, it will be greatly delayed. In a scene akin to some gruesome horror movie, the mother
repeatedly inhales mind-altering drugs in some attempt to alleviate the pain
of childbirth, and with every breath, unknowingly, ensures the gradual
destruction of the future cognitive and developmental capabilities of her soon
to be born child. Meanwhile, trapped within in the womb, continually
flooded with toxic nitrous oxide, the foetus cannot speak up to halt the
intoxication, and for many, they never will be able to speak. Whilst it is
highly unlikely that any mother would deliberately bathe the brain of her
unborn child in toxic levels of a Schedule 6 toxin, this has effectively and
irreversibly been what she has done. Little wonder, that some two to three years later, when
her child fails to achieve its milestones and potential in life, she will not
know or realize that she, and that she alone, is the reason for the child’s
failure to develop. Something that will haunt her for the rest of her life. At that time, the people who advised her that nitrous
oxide was perfectly safe for her and her unborn child will be long gone and
will be adopting a “no mia culpa” attitude, denying any culpability for the
regressed child. Little did she know, that the advice from those doctors,
nurses and mid-wives, at the very time when she should have been able to
depend upon them, and whom she trusted implicitly, was incorrect. Little did
she know, that one decision on that day would completely change her life from
one of joy and amazement and love of her child, to one of constant care,
heartbreak, frustration and depression. A life, in which many times she will
consider giving up her child to care by someone else, and in some instances
even cause her and her family to commit murder and suicide. No, Nitrous is
definitely no laughing matter, and should be avoided at all costs during those
final hours of the foetus’ life, a life that was until that moment completely
under her control.
Class Action against Nitrous Oxide There is currently a class action for
injured patients, families, and healthcare workers filed against providers and
equipment manufacturers
https://cassaction101.com/lawsuits/nitrous-oxide-lawsuit/ Even if you signed a consent form during
labour, you may file a nitrous oxide lawsuit, if the healthcare providers were
negligent or failed to inform you of specific risks - such as permanent or
delayed developmental due to inactivation of vitamin B12 through
administration of nitrous oxide during labour. We have yet to find any
hospital or Mid-wife institution that states how dangerous nitrous oxide can
be. Hospital Negligence
https://monacosolicitors.com.au/service/hospital-negligence-lawyers/
https://monacosolicitors.com.au/service/birth-injury-lawyers/
Nitrous use in the US In many ways, the current use of nitrous oxide in the US
can be blamed upon the extensive work by Judith Bishop Today it is used by 60%to 75% of laboring women in
countries such as the United Kingdom, Canada, Sweden, and New Zealand. The
United States, however, was a late adapter. In 1999, in the United States this
was all to change when Judith Rooks,CNM, MPH, FACNM, came into the picture The Campaign.
In a campaign only rivalled by that of the tobacco
industry, Judith Rooks, efforts were able to raise the use of nitrous oxide in
labour from 1% to over 50% and also successfully raise the incidence of autism
from 0.1% to 8% in the children from mothers who used nitrous. Rooks’ work
single-handedly resulted in the destruction of the brains of millions of
children. A spectacular success. Unfortunately, whilst the needs of the mother
for pain relief were, little regards was taken to the outcomes of the brain’s
of the children, who were then subjected to developmental delay and a
life-time of care. At least the mothers had no pain at the time of birth, to
the great relief of the anaesthetists and nurses who were pushing the use of
nitrous oxide. Curiously, later when the “fruits of their labour” were
revealed, these anaesthetists and nurses were nowhere to be found and denied
that their insistence in the technique and their strong reassurance that it
would do no harm to mother or baby. No mia culpa. Whilst the action of nitrous
oxide as an NMDA receptor antagonist was not determined until 1998 (some 64
years after it was first used in labour) (Jevtović-Todorović, V., Todorovć,
S., Mennerick, S. et al. Nitrous oxide (laughing gas) is an NMDA
antagonist, neuroprotectant and neurotoxin. Nat Med 4, 460–463
(1998).
https://doi.org/10.1038/nm0498-460), The action of nitrous oxide on vitamin B12 had been known
since 1979 (Nunn, 1979l) with many clinical examples of toxicity known
following that date (Vishnubhat et al, 1991; Cheng etal, 2013). In this
regard, Rook’s work was arguably worse than that of the tobacco companies work
on addiction and the use of cigarettes. When they started their campaign, the
link to cancer was not known, whereas in Rook’s case, the action of nitrous
oxide on vitamin B12 was well known. As is often the case, however, the
medical profession with their accomplices totally ignored the science. In many
regards, Judith Rooks could be regarded as the mother of modern autism in the
US Whilst it is assumed that many a mother who received pain relief as a
result of her efforts, one can but wonder as to whether they would look
equally as favourably on the 8% of children with autism and the 22% of
children with AHDH, as a result of her efforts.
Institutions contacted with no response.. Royal Children's Hospital
Patient.info@rch.org.au Australian Medical Association
ama@ama.com.au Autism Speaks, Autism CRC, Australian Society of Anaesthetists,
Dr Simon
Martel, Specialist Anaesthetist, Australian Society of Anaesthetists
contact@drmartel.com, Dr Suzanne Bowersbower@asa.org.au
Bernard Rupasinghe - Policy and Public Affairs Manager. "Your views have been
duly noted, and we value contributions from all members of the public on
issues related to anaesthesia and patient care. Please be assured that your
correspondence has been received and recorded. Should you wish to pursue this
matter further, you may wish to to direct your concerns to the appropriate
government authorities......" In other words, business as usual, we will not
be changing our current treatments. Calculations on nitrous use in labour
suggest that one four hour session with nitrous oxide is equivalent to 30
years of maximal work-related tolerated dose of 25 ppm! Clinical Excellence Queensland - Healthcare Improvement
Unit. Basically have failed to realize the known toxicity of nitrous
oxide, rather "Any consideration of changes to clinical guidance would occur
only where the required evidentiary thresholds are met, including high-quality
epidemiological evidence, prospective clinical studies, reproducible
biochemical and mechanistic validated and demonstrated clinical causation
rather than correlation"
Response This is despite the warning on the https://health.qld.gov.au
about Occupational health and safety for nitrous oxide "Prolonged occupational
exposure may cause health issues for clinicians (eg reduced fertility,
disrupted vitamin B12 synthesis)!! Curiously their recommendations are NOT for
short duration, hence "Greater user satisfaction and more effective pain
relief at 120 minutes when compared to opioid.." The response is typical of
the medical fraternity, who somehow has the belief that despite their one
in-house Occupational Health and Safety warnings about the use of nitrous
oxide, and over 130 scientific publications on inactivation of vitamin B12
with nitrous oxide, and despite setting upper limits for nitrous oxide
exposure to 25 ppm, allow the pregnant woman to imbibe 500,000 ppm nitrous
oxide ad lib for hours, and then is of the illogical belief that it will do no
harm to the foetus, which is continually bathed in a Schedule 6 toxin. Healthdirect Australia Clinical Governance Team "At present,
specialist colleges and professional bodies in Australia continue to list
nitrous oxide as an accepted option for pain relief in labour for most women
when used in recommended doses and with appropriate monitoring."
secretariat@oaa-anaes.ac.uk 14/05/2026 "Thank you
for your information. We continue to review the international evidence base,
and so we are grateful for your contribution. We will keep this on file and
continue to consider any emerging evidence and developments in this area.
At this stage, however,
we do not feel there is sufficient evidence to change our current
recommendations" Mayo Clinic
OPX@mayo.edu 14/05/2026 Lily, Patient experience representative "Thank
you for reaching out and sharing your concern with the Office of Patient
Experience. We truly appreciate you bringing this to our attention. It is
always our steadfast goal to provide excellent care and services to all our
patients. Please be assured that your concerns will be thoughtfully shared
with leadership for internal review and to inform our continuous process
improvement efforts. Mayo
Clinic values patient input and regularly partners with local teams and
leadership to enhance the patient experience, including facility improvements,
through a collaborative review process."
Minister.Jammat@dpc.wa.gov.au,
Minister.sanderson@dpc.wa.gov.au,
Dr Katherine Isoardi
katherine.isoardi@health.qld.gov.au , Dr Froessler
bernd.froessler@sa.gov.au;
Minister of Health Curtin Education
zoe.bradfield@curtin.edu.au
NSW Health
jan.fizzell@health.nsw.gov.au NSW Nurses & Midwives Association
https://www.nswnma.asn.au
gensec@nswnma.asn.au QLD Nurses & Midwives Union
memberconnect@qnmu.org.au
VIC Nurses and Midwives Association
records@anmfvic.asn.au
Clinical Practice Guidelines : Nitrous Oxide - oxygen mix Curiously the Australian Journal of General Practice warns:
Nitrous oxide exerts its neurotoxicity through vitamin B12 inactivation, which
disrupts myelin sheath maintenance, leading to peripheral and central nervous
system demyelination. See
Nitrous) Yet despite this both the
Royal Women's Hospital and
Australian Institution of Health and Welfare, recommend Nitrous oxide, as
too Mater Hospital. When contacted about the link to ASD and CFS in the
mothers, Response from Bronwyn Jenner (General Manager/Director of Clinical
Services) "I am writing to acknowledge the information you provided to the
Mater regarding the use of nitrou oxide during labour. Thank you for taking
the time to provide use with the information".
This directly infers that either they did not have the information before, or
they had it and were doing nothing about it. There are no warnings about
nitrous on their web-site. R Nitrous Oxide is known to
interfere with Vitamin B12 and folate metabolism. • Megaloblastic bone marrow
changes can be detected following exposures of several hours. Absolute
contraindications • < 12 months or 10 kg. (one would presume that this
would mean a child in the womb!!) Increased risk of nitrous oxide induced bone
marrow suppression, neurotoxicity, or increased homocysteine level: methionine
synthetase deficiency, homocystinuria and methylmalonic academia
Recommendations from Royal Womens hospital - The gas given to women in labour
is a mixture of nitrous oxide mixed with oxygen....There are no after effects
for you or your baby. (Contacted)
Mistaken beliefs Despite over 100
references on inactivation of vitamin B12 by nitrous oxide, there is the
mistaken belief of some members of the anaesthetic association that "injury
from a single episode of medical use is rare. The inactivation only affects
the vitamin B12 at the time of exposure. Any new vitamin B12 and enzyme
produced will not be affected, and so effects on vitamin B12 or methionine
levels should be short lived". Clearly these individuals do not know that
vitamin B12 loading of the brain predominantly happens in utero, and following
this, transport into the brain is almost non-existent, hence new vitamin B12
will not even reach the brain. The future - it is not good
If, as it is ascertained on this page, the increased
use of nitrous oxide is responsible for the increased rate of autism, then for
those who use nitrous oxide they have an 8% chance of having a child with
autism, and a 22% chance of having a child with ADHD. Hardly something that
should be ignored!!!! YET it has been by every Institution that we have
contacted. Hazardous Chemical Information System.
Recommends exposure to no more than 25 ppm. 50% nitrous is 20,000 times this
amount! Upper limit 50 ppm. "This level was set to :prevent embryofetal
toxicity in humans (resulting in an increased risk of spontaneous abortion)
and significant decrements in human psychomotor and cognitive functions or
other adverse health effects in exposed personnel". Queensland Health. "It
is widely accepted the N2O has limited value in modern anaesthesia. Its
declining use in anaesthesia is due partly to improved alternatives and partly
to the growing environmental conscience of anaesthetists."
Addendum on the use of Nitrous in Labour The
recommended safety guidelines for exposure appear to have an upper limit of 25
ppm, but the pregnant woman receives a 50% mixture of Nitrous Oxide gas,
which would be 500,000 ppm, so 20,000 times more than the upper recommended
limit. The 25 ppm limit is an occupational exposure
standard for ambient air in workplaces such as dental surgeries,
operating theatres, and labour wards. It is designed to protect staff,
not patients. This value appears consistently across authoritative sources: This means that over an 8‑hour shift, the average concentration of
nitrous oxide in the room air should not exceed 25 ppm. In contrast, a labouring woman inhales a 50% nitrous oxide / 50%
oxygen mixture from a demand‑valve mask. with the inspired concentration is 500,000 ppm,
thus the inhaled concentration is 20,000 times
higher than the occupational exposure limit. The 500,000 ppm is the deliberate inspired concentration for
the mother on demand. Mothers with a higher pain tolerance will inspire much
less than those with a lower pain tolerance, The nitrous oxide, though is a
dual action molecule, not only is it an NMDA receptor antagonist, it is also a
neurotoxin and as time and dose increases more and more methionine synthase is
inactivated as NO-Co(III)B12 is formed. In contrast to the mother, the fetus, is not a “patient” receiving analgesia,
rather the fetus is an unintended recipient of a high‑dose
anesthetic/neurotoxic gas with no therapeutic justification. A gas which NIOSH
has explicitly stated that nitrous oxide exposure
impairs cognitive and neuromotor performance. Further, in contrast to the mother, the fetus has:
direct placental transfer of N2O, which has a
higher brain‑to‑body ratio,
immature detoxification systems,
active neurodevelopmental processes, vulnerability to methionine synthase inhibition,
and cannot readily expel the gas via its lungs. “Workplace safety authorities restrict nitrous oxide
exposure for staff to 25 ppm, yet a labouring woman inhales 500,000 ppm
— a concentration 20,000 times higher. The fetus, which receives no
analgesic benefit and is uniquely vulnerable to methionine synthase
inhibition, is exposed to the same concentration. This represents a profound
inconsistency in safety standards.” Nitrous Oxide - A Schedule 6 poison Since 1 October, 2022, nitrous oxide for non-therapeutic
use has been nationally classified as a Schedule 6 poison. In addition, as for
ALL Schedule 6 poisons, nitrous oxide cannot be supplied to anyone under 16
years-of-age. In contrast, Nitrous oxide, used for therapeutic purposes,
including for analgesia is nationally classified as a Schedule 4 medicine.
This, though raises a new legal and ethical frame, in that there is a
statutory principle "The protection of minors from involuntary exposure to a
toxic inhalant." This effectively means that the Nitrous oxide, a Schedule 6
poison has been supplied to a minor without consent. The foetus is
involuntarily exposed to the gas, from which it receives no therapeutic
benefit. The nitrous has been supplied at 20,000 times higher than the
occupational limit. The exposure is not incidental it has been knowingly, and
clinically administered to the foetus. This exposue occurs during the period
of highest neurodevelopmental vulnerability. The timing of nitrous exposure is critically
important. The month before term is one of the most metabolically
intense periods in human neurodevelopment, and the processes that dominate
this window are precisely the ones most vulnerable to methyl‑B12 inhibition,
methionine synthase blockade, and creatine‑dependent energy failure. Parts of the fetal brain that are most active in the
month before term Late gestation (≈36–40 weeks) is dominated by three
major neurodevelopmental processes: A. Rapid myelination (oligodendrocyte maturation) In this regard Myelin synthesis requires: Methionine synthase inhibition directly compromises all
three. B. Synaptogenesis and dendritic arborisation This is the period when: These processes require: This is also when the cortex undergoes its final “wiring”
phase. C. Growth of subcortical structures Particularly: These regions are: The cerebellum, in particular, undergoes a massive
growth spurt in the last month before birth. Hence, these processes are
more active as the foetus approaches term. Premature infants have less mature brains
because these processes accelerate near term. The last 4–6 weeks include: The closer to term, the more intense the
neurodevelopmental activity — and the higher the metabolic and methylation
demand. This means the fetus at 38–40 weeks is more vulnerable,
not less. Higher neurodevelopment activity increases demand on
methionine synthase A. Methylation demand skyrockets Late gestation requires: All of this depends on: Methionine synthase + SAM=> methylation + SAH Nitrous oxide irreversibly inactivates methyl‑B12,
shutting down methionine synthase. B. Creatine synthesis depends on methylation Creatine synthesis requires: So when methylation falters: This aligns with the observation that ASD children
have lower serum creatinine. C. Aconitase and mitochondrial metabolism are also
vulnerable Nitrous oxide exposure increases:Oxidative stress,
Homocysteine, S‑nitrosylation Aconitase is exquisitely sensitive to these, impairing:
:TCA cycle flux
ATP generation,
Neuronal energy stability The Foetus at term is under higher metabolic demand
and therefore more vulnerable to nitrous oxide In the final month before birth, the fetal brain enters
its most metabolically intense phase of development, characterised by rapid
myelination, explosive synaptogenesis, and accelerated growth of the
cerebellum, thalamus, and basal ganglia. These processes demand exceptionally
high rates of methylation and creatine‑dependent energy buffering, both of
which rely on uninterrupted methionine synthase activity. Nitrous oxide
irreversibly inactivates methyl‑B12, shutting down methionine synthase at the
very moment when the near‑term fetus requires maximal methylation flux to
support membrane synthesis, dendritic arborisation, and neuronal energy
stability. This creates a profound biological vulnerability: the fetus at term
is not less sensitive to nitrous oxide but markedly more so, because its
neurodevelopmental machinery is operating at peak intensity and therefore at
peak dependence on the very pathways nitrous oxide disrupts. Perhaps one
could not think of a more perfect time to inflict damage upon the child Rebuttal: Why Short‑Term
Neonatal Assessment Cannot Be Used to Infer Long‑Term Neurodevelopmental
Safety of Nitrous Oxide Exposure It is not scientifically defensible to infer long‑term neurodevelopmental
safety of fetal nitrous oxide exposure from normal neonatal appearance or
short‑term postnatal observations. Autism, developmental delay, and other
neurodevelopmental conditions are behavioural diagnoses made
months to years after birth using structured criteria and specialist
assessment. They cannot be identified in the first hour, day, or even week of
life, and their assessment lies entirely outside the remit and expertise of
the anaesthetist. Consequently, reassurance based on a normal neonatal examination provides
no meaningful evidence regarding the absence of long‑term
neurodevelopmental effects of nitrous oxide exposure in utero. Equally problematic is the implicit assumption—sometimes stated, sometimes
simply presumed—that nitrous oxide can act selectively on maternal NMDA
receptors without materially affecting the fetus. This assumption is not
supported by basic physiology or biochemistry. Nitrous oxide is a small, inert
gas that crosses the placenta freely. The same molecule that produces maternal
analgesia and euphoria via NMDA receptor antagonism is also known to
irreversibly inactivate methionine synthase by oxidising the Co(I)
form of methylcobalamin. Fetal methionine synthase activity is lower at baseline
and more vulnerable to inhibition than maternal enzyme at the
same exposure. Thus, while the mother experiences transient, reversible
analgesia as her brain nitrous oxide concentration rises and falls with each
inhalation, the fetus is subjected to a cumulative, time‑dependent
inactivation of methionine synthase throughout the exposure period. Although nitrous oxide is rapidly eliminated via the maternal lungs once
administration ceases, the fetus has no independent route of excretion.
Fetal elimination depends entirely on placental transfer back into the
maternal circulation. During ongoing maternal use, this results in a state of
continuous fetal exposure, even as maternal brain
concentrations fluctuate in a wave‑like pattern. Taken together, these considerations make it untenable to claim that the
fetus is unaffected by nitrous oxide, or that normal short‑term neonatal
observations can be taken as evidence of long‑term neurodevelopmental safety.
Any assertion to the contrary rests on assumptions that are physiologically
implausible and inconsistent with established biochemical mechanisms."
The decision by the medical profession to
ignore over 100 publications on the dangers of nitrous oxide, and its ability
to irreversibly inactivate methionine synthase. And then openly advertise
nitrous as being safe for mother and baby, has arguably been the most
significant factor in the rapid increase in the rate of asd and adhd.
Nitrous Oxide and Vitamin B12 deficiency
Russell-Jones, GJ.
Vitamin B12,
Nitrous Oxide Use During Labor and Autism Med Clin Case Rep. 2026; 6(1): 1-7.
https://doi.org/10.33425/2768-6647.1074
Gregory John Russell-Jones.
Developmental Delay in Children Due to Inactivation of Methionine Synthase by
Nitrous Oxide During Labour. J Med - Clin Res & Rev. 2026; 10(3): 1-7.
https://www.scivisionpub.com/journals/journal-of-medical-clinical-research-reviews/articles/in-press
https://www.youtube.com/shorts/X1Q8U45SMAE
https://b12oils.com/MCRR-26-791NitrousASD.pdf
Gregory
Russell-Jones Nitrous oxide use in labour, NO, it is not safe for mother or
child. J Med - Clin Res & Rev. 2026; 10(5): 1-7https://www.scivisionpub.com/pdfs/nitrous-oxide-use-in-labour-no-it-is-not-safe-for-mother-or-child-4366.pdf).
Reduction in use of Nitrous oxide
Dimic, N., Djuric, M., Nenadic, I. et
al. Nitrous
Oxide — Application in Modern Anesthesia. Curr
Anesthesiol Rep 13,
117–123 (2023).
https://doi.org/10.1007/s40140-023-00554-4
Natale I, Jani S, Alcaino E, Swain L, Skowno J. Clearing the Air: Nitrous Oxide
in Australian Paediatric Practice. J Paediatr Child Health. 2026 Jan;62(1):6-15.
doi: 10.1111/jpc.70244. Epub 2025 Nov 26. PMID: 41305937.
Nitrous oxide: What is it and
how dangerous is it?
Copyright © 2018 B12 Oils. All Rights Reserved.
Nitrous Oxide, vitamin B12 and Autism
Vitamin B12 Distribution in the
body, a two pool system












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