As blogged previously, GLP1 medications [eg semaglutide (Ozempic/Wegovy) , tirzepatide (Mounjaro/Zepbound] are currently contraindicated (must not be used) before or during pregnancy because we don’t have safety studies in conception/pregnancy, and because weight loss is not recommended during pregnancy.

Now here’s the context: Some women are taking GLP1 medication to optimize their health and weight before pregnancy. Some women with elevated weight and infertility due to polycystic ovary syndrome (PCOS) are taking GLP1 medication to try to improve their fertility and PCOS with weight loss. So it is perhaps not surprising that accidental pregnancies are happening amongst the millions of women around the world taking these treatments. Also, given that weight is regained along with regression of health benefits after GLP1s are stopped, women and their doctors have a lot of questions about the pros and cons of GLP1 use before pregnancy (as blogged here).

In light of this, a recent and provocative article in Obesity Reviews suggests that the hesitation to study GLP1s in pregnancy is consistent with a harmful protectionist ethic, and that strong ethical analyses routed in reproductive justice are critical to filling this evidence gap.

The paper gives a very interesting discussion on the protectionist culture of excluding pregnant women from clinical trials and research, for fear of a bad outcome (eg birth defects). The downside of this is that we have little information on medication safety in pregnancy in general, GLP1s included. One study suggested that nearly 97% of pregnant women take at least one medication in pregnancy, and 96% take at least one medication during the first trimester (when most of fetal organ development is happening). Almost 98% of drug treatments approved for general use in non-pregnant people between 2000-2010 are listed as ‘undetermined’ teratogenic (birth defect) risk, and for 73% of these drugs, the amount of data regarding safety in pregnancy is nil. The authors comment that the result of this protectionist ethic is a ‘failure to critically consider risk in clinic research during pregnancy, failure to make drugs safer, and failure to make pregnant people or their children safer’.

In regard to GLP1s, this vast gap in knowledge can only currently be filled by databases collecting information on accidental pregnancies with GLP1 on board – reassuringly, no association between accidental use of GLP1 around the time of pregnancy and birth defects has so far been found.

How could the medical community carefully approach study of GLP1 use in conception/pregnancy? The authors suggest considering careful clinical trials with women who have ‘more barriers ahead of them to delivering a healthy child while preserving their own health‘, such as individuals with elevated BMI at high risk of hypertensive disorders of pregnancy (HDP) (eg history of severe HDP or HELLP syndrome that threatened her life in the past), and that these women ‘deserve high quality research in pregnancy that can make their pregnancies safer and improve their own health as well as that of their offspring’. Another layer to add in here could be to start studies with use in the third trimester only (well after organ formation is complete) and expand studies gradually earlier in pregnancy if those studies prove benefit and safety.

BOTTOM LINE: As per this article, ‘protecting pregnant people from risk in research, rather than protecting them through research to reduce clinical risk’ leaves clinicians and patients empty-handed of knowledge on the dangers or benefits of GLP1 use before or during pregnancy. Authors suggest that ‘arriving at appropriate and minimized amounts of risk in well-controlled research settings is important to prevent shifting a greater amount of risk through uncertainty and lack of evidence to the less controlled clinical setting’. Note that unless/until we have data, GLP1 medications remain contraindicated (must not be used) before or during pregnancy.

Disclaimer: I am/have been an investigator in clinical trials of semaglutide and tirzepatide.   I receive honoraria as a continuing medical education speaker and consultant from the makers of semaglutide (Novo Nordisk), and tirzepatide (Eli Lilly).

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