Are Weight Loss Drugs Safe During Pregnancy?

As more people take popular diabetes and anti-obesity injectable medications, more questions about their lifestyle impact are bound to emerge. A big one right now, given the “Ozempic babies” phenomenon, is what to do if you happen to become pregnant while taking one of these drugs.

The Ozempic website states that it’s important to talk to your healthcare provider if you’re pregnant or plan to become pregnant, while Wegovy’s site says that the medication “may harm your baby.” However, a new study showed that GLP-1 receptor agonists—the class of drugs Ozempic and Wegovy belong to—are safe to use during pregnancy in people with type 2 diabetes. As the uptake of these drugs increases, are doctors learning more about their impact during pregnancy?

Researchers and doctors alike still know very little about how these medications can impact pregnant humans.

“There is limited data on safety of GLP-1 agonists in pregnant women,” Rashika Bansal, MD, assistant professor in the Division of Endocrinology at Rutgers Robert Wood Johnson Medical School, told Verywell. “The main concerns with using GLP-1 receptor agonists during pregnancy are potential effects on the developing fetus.”

Animal studies have shown an increased risk of birth defects, miscarriage, and babies being born small for their age, “but clear evidence in humans is lacking,” Bansal said. Because doing any kind of clinical trials with pregnant humans is difficult due to potential safety issues, doctors generally recommend not using these medications during pregnancy to be safe.

“The FDA has not recommended these medications to be safe for use during pregnancy—that would be off-label use,” Mir Ali, MD, a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, California, told Verywell.

Emerging Research Compares Diabetes Medications During Pregnancy

Some research suggests that GLP-1 usage during pregnancy might not be so risky. A recent study published in JAMA Internal Medicine found that people with type 2 diabetes who took GLP-1 drugs during pregnancy had no greater risk of birth defects or other adverse outcomes than those who took insulin during pregnancy.

However, the study period was from 2009 through 2020, so GLP-1 use wasn’t as robust for the entire period. As a result, the researchers lumped all GLP-1s together. Researchers also examined the impact of other second-line diabetes medications on pregnancy, including sulfonylureas, DPP-4 inhibitors, and SGLT2 inhibitors.

“This study was part of a larger goal of my collaborators and I to study the safety of medications used to treat type 2 diabetes during pregnancy, specifically with regards to malformation risk in the infants,” lead study author Carolyn Cesta, PhD, assistant professor in the Centre for Pharmacoepidemiology at Karolinska Institutet in Sweden, told Verywell. “The prevalence of type 2 diabetes has been increasing amongst reproductive-aged women globally, leading to more use of these medications in pregnant women, and therefore the need for more information.”

It’s important to point out that people with type 2 diabetes are already at an increased risk of having a child with birth defects to begin with, including congenital heart defects and central nervous system defects. Of the 3.5 million infants in the study, the standard prevalence of birth defects was 3.7%, compared to 5.3% among infants born to women with type 2 diabetes. However, research has found that the risks can be reduced by pre-pregnancy counseling and strict control of the woman’s blood sugar levels during pregnancy.

But while the study found that the risk of birth defects associated with taking GLP-1 drugs during pregnancy was similar to those from taking insulin (8.3% vs. 7.8%), Cesta said there’s still more work that needs to be done.

“Whether GLP-1s are used for type 2 diabetes or for obesity, there is not enough evidence on their safety for use during pregnancy, and the recommendation is that GLP-1s are to be discontinued at least two months prior to conception,” she said. “Of course, not all pregnancies are planned, so women who discover they are pregnant while using GLP-1s should consult with their doctor. The plan should be to discontinue.”

For people who have type 2 diabetes, next steps would likely involve switching to a medication with a known safety profile, like insulin, she said.

What Happens If You Stop Using GLP-1 Medications During Pregnancy?

If you discover that you’re pregnant while taking a GLP-1 drug, doctors say it is safe to simply stop taking it. “There is no need to taper off,” Ali said.

However, there is a risk of regaining weight you’ve lost, Bansal said. “Stopping this medication anytime—whether pregnant or not—does carry the risk of weight gain and return of appetite,” she said.

If you’re planning to try to conceive, doctors recommend stopping your medication two months before you start trying.

“We advise switching to alternate methods of weight management in patients planning pregnancy and try to stop this medication in the preconception period,” Bansal said. “This prevents the abrupt stopping of the medication during pregnancy.”

But conception doesn’t always go according to plan. Data shows that almost 45% of pregnancies in the U.S. are unplanned. If you find out that you’re pregnant while taking Ozempic or a similar medication, Ali recommends that you stop taking it and contact your doctor about next steps.

“It’s recommended that you stop right away,” he said. “There’s no real withdrawal other than you might feel more hungry than you have been.”

The medication is taken on a weekly basis, which should also give people who use it for blood sugar management time to get in touch with their doctor before it’s time for the next dose.

Ultimately, Cesta said that more data is needed.

“We absolutely need more research on many aspects, including larger studies investigating whether there is a risk of malformations in the GLP-1-exposed infants and whether there are longer-term risks in the children,” she said.