Even women trying to have children ‘should be told to avoid smoking cannabis over fears it may raise the risk of birth defects’
- Study on mice found some developed birth defects when exposed to THC
- Impact was only observed on mice with a genetic mutation to cell development
- Scientists warned that the finding means prospective mothers should avoid pot
Even women trying to have children should be told to avoid smoking cannabis over fears it may raise the risk of birth defects, experts said today.
NHS bosses and other health agencies across the world already say mothers-to-be should steer clear of the drug.
But now scientists at Icahn School of Medicine at Mount Sinai say consumption may be ‘inadvisable’ even for women trying to get pregnant.
The warning comes on the heels of a study on pregnant mice, which saw academics purposely expose them to THC.
THC is chemical component of cannabis responsible for giving people the sensation of feeling ‘high’.
A study on mice found that some could develop a brain and face defect in the womb when exposed to THC a finding that prompted the scientists in the study to warn women trying to conceive about the possible danger of using the drug
What are the pros and cons of cannabis?
Cannabis is an illegal Class B drug in the UK, meaning possession could result in a five year prison sentence and those who supply the drug face up to 14 years in jail.
However, the drug is widely used for recreational purposes and can make users feel relaxed and happy.
But smoking it can also lead to feelings of panic, anxiety or paranoia.
Scientific studies have shown the drug can alleviate depression, anxiety and stress, but heavy use may worsen depression in the long term by reducing the brain’s ability to let go of bad memories.
It can also contribute to mental health problems among people who already have them, or increase users’ risk of psychosis or schizophrenia, according to research.
Marijuana can be prescribed for medical uses in more than half of US states, where it is used to combat anxiety, aggression and sleeping problems. Researchers are also looking into whether it could help people with autism,eczema or psoriasis.
Cannabis oil containing the psychoactive chemical THC, which is illegal in the UK, is claimed to have cancer-fighting properties, and one 52 year-old woman from Coventry says she recovered from terminal bowel and stomach cancer by taking the drug.
Pups of pregnant mice with a genetic vulnerability who were exposed to THC were born with holoprosencephaly — where the brain and face fails to form correctly.
Expectant mice carrying the same mutation who weren’t exposed to THC didn’t have offspring with the same defect.
And pups without the mutation who were exposed to the cannabis chemical also did not develop the condition.
Lead researcher Dr Robert Krauss, an expert in cell, developmental and regenerative biology, published the findings in the journal Development.
He added: ‘Our results show that embryos are sensitive at a very early period, before many women know they are pregnant.
‘Cannabis consumption may, therefore, be inadvisable even when women are trying to get pregnant.’
Dr Krauss warned the findings were of importance because THC concentrations of cannabis are now ‘very high’.
Skunk — which makes up most of the cannabis sold on Britain’s streets — contains more THC than traditional strains.
It is purposely created by dealers aiming to make the most potent strain of the drug possible in order to maximise their profits.
And Dr Krauss warned the study also raised questions on the impact of CBD, which is said to have an array of medicinal benefits.
He added: ‘As CBD is widely available and often viewed as beneficial – or at least innocuous – it would be worth investigating this as well.’
Scientists exposed pregnant mice to THC about a week after conception.
They then followed the development of the mice pups, including some which carried a mutation weakening a crucial mechanism involved in brain cell development called ‘Hedgehog signalling’.
Holoprosencephaly occurs in one out of 250 human conceptions, according to the National Organization for Rare Diseases.
The NHS currently advises pregnant women against smoking cannabis, stating that using it regularly could affect a baby’s brain development as they get older. But it says the drug has not been linked to birth defects.