Stopping blockbuster weight loss drugs before pregnancy linked to greater weight gain, health risks

Women who stop taking weight loss drugs before or early in their pregnancies tend to gain more weight and have more health issues, a new analysis has found.

Compared with women who had never taken these drugs, they appear to be at higher risk of preterm birth, diabetes, and high blood pressure conditions related to pregnancy, for example, preeclampsia, according to the study, which was published in the journal JAMA.

Blockbuster anti-obesity and diabetes medicines such as Ozempic and Wegovy are part of a class of drugs known as glucagon-like peptide-1 (GLP-1) receptor agonists, which help people lose weight by mimicking a hormone that reduces their appetite.

People oftenregain weight when they stop taking these medicines, but pregnant womenare not advised to take them. That’s prompted debate over how to help women wean off the drugs around the time they’re having children – without raising other health risks related to diabetes or obesity.

Weight loss drugs’ popularity has “increased dramatically, but recommendations suggest their discontinuation before pregnancy because there's not enough information about their safety for unborn babies,” said Dr Jacqueline Maya, the study’s lead author and a paediatric endocrinologist at Mass General Brigham for Children.

“We sought to assess how such discontinuation affects weight gain and outcomes during pregnancy,” she added in a statement.

Maya’s team analysed health data for nearly 1,800 pregnancies between 2016 and 2025, mostly among women with obesity.

Women who stopped taking GLP-1 medicines before or early in pregnancy gained an average of 7.2 pounds (3.27 kilograms) more during pregnancy than women who did not take the drugs, the study found.

The GLP-1 group also had a 32 per cent higher risk of gaining more weight than was recommended during pregnancy, a 30 per cent higher risk of diabetes, a 29 per cent higher risk of hypertensive disorders, and a 34 per cent higher risk of preterm birth.

Notably, there was no difference in C-section risk or the babies’ birth weight or length.

Dr Camille Powe, one of the study’s authors and an endocrinologist at Mass General Brigham, said more research is needed to weigh the pros and cons of taking weight loss drugs around the time of pregnancy.

“We need to do more research to find ways to help manage weight gain and reduce risks during pregnancy when stopping GLP-1 medications,” Powe said.