You’ve heard of the rise of “Ozempic babies” — where women who’ve previously struggled with infertility get knocked up on GLP-1s — but new research shows that going off those drugs may have a negative impact on pregnancy.
A new study from Mass General Brigham found that women who stopped taking popular GLP-1 medications before or shortly after conceiving gained significantly more weight during pregnancy than women who had never taken them.
More concerning, they also faced higher odds of serious pregnancy complications that can put both mother and baby at risk, including one of the leading causes of maternal death in the US.
The findings come as the drugs’ popularity continues to soar. Nearly 12% of Americans have used GLP-1s for weight loss alone, while many others rely on them to treat conditions such as type 2 diabetes.
Inside the body, the medications work by mimicking hormones released by the gut after eating, helping regulate blood sugar, slow digestion and keep people feeling full longer.
But what happens to fetuses whose mothers take these drugs — or even to women who stop them before becoming pregnant — remains largely unknown.
“The use of glucagon-like peptide-1 receptor agonists — or GLP-1RAs — has increased dramatically, but recommendations suggest their discontinuation before pregnancy because there’s not enough information about their safety for unborn babies,” Dr. Jacqueline Maya, a pediatric endocrinologist and lead author of the study, said in a press release.
“We sought to assess how such discontinuation affects weight gain and outcomes during pregnancy.”
To find out, Maya and her team analyzed electronic health records from 1,792 pregnancies delivered within the Mass General Brigham healthcare system between 2016 and 2025.
The women, who averaged 34 years old and were classified in the obese BMI category, had all taken GLP-1 medications within three years before becoming pregnant or up to 90 days after conception.
To compare outcomes, each mom-to-be was matched with three pregnancies from mothers who had never used the drugs.
The researchers found that women who stopped taking the medications before or early in pregnancy gained an average of 7.2 more pounds than those who’d never taken them.
They were also 32% more likely to experience excess weight gain, meaning they put on more pounds than recommended during pregnancy.
That tracks with previous research showing that many patients regain weight quickly after stopping GLP-1s, once the drugs’ appetite-suppressing and fullness-promoting effects wear off.
But the risks didn’t stop at the scale.
The study also found that women with a history of GLP-1 use had a 30% higher risk of developing gestational diabetes, a condition marked by high blood sugar during pregnancy.
Gestational diabetes affects about 9% of US pregnancies each year and often resolves after delivery. It can usually be managed with diet, exercise, blood sugar monitoring and sometimes medication.
Left uncontrolled, however, it can cause serious problems. Babies may face a higher risk of low blood sugar at birth, obesity later in life and other health issues, while mothers are more likely to develop complications such as type 2 diabetes and heart problems.
The study also found that women who had taken GLP-1s before getting pregnant or early in their pregnancy had a 34% higher risk of preterm delivery, meaning their babies were born before 37 weeks.
They were also 29% more likely to experience hypertensive disorders during pregnancy (HDPs), which are cases of high blood pressure that can exist before pregnancy or develop during it.
Unmanaged HDPs are strongly linked to severe maternal complications, including heart attack and stroke, and are a leading cause of pregnancy-related death in the US, according to the CDC.
If left untreated, these disorders can restrict blood flow to the placenta, making it harder for the baby to get the nutrients it needs. This can lead to complications such as fetal growth restriction, preterm birth and even stillbirth.
But there was one bit of reassuring news: The researchers found no increased risk of Cesarean delivery, or of babies being born with unusually high or low birth weight or abnormal birth length.
Still, the authors say the findings highlight a major gap in care for women who rely on GLP-1 drugs before getting pregnant.
“Additional studies are needed on the balance of pre-pregnancy benefits of GLP-1s with the risks associated with interrupting them for pregnancy,” said Dr. Camille E. Powe, co-director of the Diabetes in Pregnancy Program at Massachusetts General Hospital and senior author of the study.
“We need to do more research to find ways to help manage weight gain and reduce risks during pregnancy when stopping GLP-1 medications.”
