Using popular weight-loss drugs like Ozempic during pregnancy is not recommended. But stopping the medications just before conception or in the early stages of pregnancy may come with some risks, according to a new study. And without further research, say experts, the data paints a complicated picture of the relationship between GLP-1s and pregnancy.
What did the study find?
Discontinuing GLP-1s before or during pregnancy is associated with more gestational weight gain when compared to not taking them, according to the observational study published in JAMA. It also results in a higher risk of preterm delivery, hypertensive disorders of pregnancy, and gestational diabetes, which is linked to a greater risk of developing Type 2 diabetes later in life.
Researchers from Boston’s Mass General Brigham reviewed medical records from almost 150,000 pregnancies between June 2016 and March 2025. Among the 448 who had taken GLP-1s, 65% were more likely to gain more weight than recommended during pregnancy, compared with 49% of 1,344 pregnancies that did not take GLP-1s.
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But the analysis has “key limitations,” said Live Science. Women who did and did not take the drugs “may not have been completely comparable,” and the study was “not designed to capture potential benefits of taking Ozempic or a similar drug before pregnancy.”
Due to the documented weight gain associated with discontinuing the drugs outside of pregnancy, the increases shown in the study are not surprising, pediatric endocrinologist and lead study author Jacqueline Maya said to Medscape Medical News. The team was “reassured that there were no changes in infant birth weight,” but they were “concerned that there were increases in the risk of obstetric outcomes,” said Maya. Still, given the limitations of observational studies, they could not determine whether stopping the medications directly caused the adverse outcomes.
What remains unanswered?
According to Maya, the study points out potential risks that need closer monitoring and “underscores the need for new strategies to support patients during the transition off these medications,” said The Washington Post. The findings highlight critical gaps in care and can help influence future studies, clinical counseling and approaches to weight management during pregnancy.
Some experts believe the study should clarify who actually used the medication, since the study relies on medical records of people who were prescribed the drug but does not “confirm whether they took the medications,” said the Post. Another limitation noted in the study is that researchers measured the degree of obesity among the women based on their weight after GLP-1-related weight loss rather than at their initial higher weight.
This approach of comparing different cohorts of patients is “not matching apples to apples” and may underestimate the benefits of reducing obesity before pregnancy, Taraneh Soleymani, an associate professor of medicine and the director of obesity medicine at Penn State College of Medicine, who was not involved in the study, said to the Post. While safety concerns based on animal studies mean GLP-1 drugs must be stopped before pregnancy, that does not diminish the benefits they have on obesity before conception, she added.
One question that still needs to be answered is the optimal timing for discontinuing GLP-1s to ensure optimal pregnancy outcomes, said Maya to Medscape Medical News. Experts should “exclude any potential long-term impact on childhood metabolic health,” she added. These medications are known to be “beneficial for weight, blood sugar and cardiovascular health,” so the focus must be on “finding ways to support women who come off these medications for pregnancy.”
