Popular anti-anxiety medication could be putting more than 1 million pregnant women at risk of miscarriage, a new study suggests.
Researchers from Taiwan studied more than 3 million pregnancies in 2 million women and found 4.4 percent – or 136,130 – resulted in miscarriages.
They analyzed the medical history of all the women studied, and found those prescribed a class of drug called benzodiazepines – used to treat anxiety, depression and insomnia – were, on average, 70 percent more likely to miscarry compared to those who didn’t take the pills.
Benzodiazepines, also called benzos, are a group of sedative drugs. The most well known medications include Xanax, Valium, Ativan and Klonopin.
The researchers also noted this increased risk stood even when other co-founding factors, like age and health of the woman, were accounted for.
Benzodiazepines, also called benzos, are a group of drugs used to treat insomnia, seizures and anxiety disorders. The most well-known medications include Xanax, Valium, Ativan and Klonopin
The scientists also said their findings highlight the necessity for healthcare professionals to ‘meticulously balance the risk-benefit ratio when considering the use of benzodiazepines to treat psychiatric and sleep disorders during pregnancy.’
It is estimated that approximately 1.7 percent of pregnant women (around 1.2 million) are prescribed these medications during the first trimester of their pregnancy – a number that has been on the rise in recent years.
The study, published in the journal JAMA Psychiatry, looked at miscarriages among women exposed to benzos before getting pregnant only, during pregnancy only and during both time periods.
Long-acting benzos -drugs processed more slowly in the body, such as Valium, showed an increased risk of miscarriage of 67 percent, while short-acting benzos, like Versed showed a 66 percent increased risk.
Alprazolam, the generic version of Xanax, showed the lowest risk association, at 39 percent.
When used during pregnancy, benzos can cross the barrier between the mother and the placenta, exposing a fetus to the drugs.
Researchers hypothesized that because of the role benzodiazepines play in the development and growth of cells, it is plausible benzodiazepine exposure may cause fetal developmental abnormalities, which could ultimately lead to miscarriage.
While the study shows an association between benzos and miscarriages, researchers cannot determine a direct link.
The investigators did account for underlying conditions that may have triggered miscarriage, but did not consider the impact of a combination of factors – like smoking and anxiety, for instance.
The findings are of note given the high numbers of pregnant women thought to be taking the medicine.
A 2020 study found the international prevalence of benzos during pregnancy was 1.9 percent.
Meanwhile another 2019 study found two percent of pregnant women received at least one benzodiazepine during pregnancy.
The Centers for Disease Control and Prevention (CDC) showed fewer than one in 100 women took a benzodiazepine or antipsychotic medication during pregnancy.
The CDC said researchers are not sure whether birth defects or pregnancy complications are linked to the medications themselves or to the underlying mental conditions these medications are used to treat.
And women who took these types of drugs were more likely to have other factors that could lead to an increased chance of birth defects and pregnancy complications.
Studies on the impact of benzos on pregnancy and fetuses have returned mixed results.
A 2022 study of more than 1.5 million children found benzodiazepine exposure during pregnancy was not associated with increased risks of neurodevelopmental disorders in children.
The American College of Obstetricians and Gynecologists, a group of OB-GYN doctors that provide medical recommendations for healthcare professionals and patients, stated that studies show most antidepressants, which could include benzos, do not increase the risk of birth defects.
However, a 2020 study by Stanford University researchers found women who took benzos in the week before conceiving had a 50 percent higher risk of having an ectopic pregnancy – a pregnancy that develops outside of the uterus, which is deadly to both the fetus and mother.
