December 27, 2023

expert reaction to study of benzodiazepine and miscarriage

A study published in JAMA Psychiatry looks at benzodiazepine use and the risk of miscarriage. 

Prof Christiaan Vinkers, Psychiatrist and Stress & Resilience chair, Amsterdam University Medical Centre, said:

“This is a very large case-control study, but I think these results have a large risk of confounding by indication, i.e. patients with mental health problems receiving more benzodiazepines.

“Benzodiazepine use is very broadly defined, and more stringent definitions lead to attenuated associations. Without a plausible mechanism, and pharmacological assumptions about short-acting vs. long-acting that are untenable, it seems to me that this study should not change current practice.

“Of course, we should always be prudent during pregnancy with any medication use. However, anxiety and severe insomnia undoubtedly also have detrimental effects on the mother and unborn child.”

Prof Sir Simon Wessely, Regius Chair of Psychiatry at King’s College London, said:

“This is what we call a ‘case control study’.  It’s well conducted with big numbers, and I am in no doubt that they found an association.  But the big question is, is this cause and effect?  And the problem is we can’t tell.  There may be plenty of reasons why someone is being prescribed benzodiazepines and is also at higher risk of miscarriage.  They did the best they could to control for these, and the association remained, but it’s always an issue in this kind of study.  The main lesson is that for lots of reasons we should continue all efforts to reduce the prescriptions of benzodiazepines anyway, especially for anything more than a very short period.”

‘Benzodiazepine Use During Pregnancy and Risk of Miscarriage’ by Lin-Chieh Meng et al. was published in JAMA Psychiatry at 4pm UK time on Wednesday 27 December 2023.

DOI: 10.1001/jamapsychiatry.2023.4912

Declared interests

Simon Wessely: I have no conflicts to declare.

Christiaan Vinkers: no COI.