GLP-1 Medications and Pregnancy: Safety, Stopping Points, and What Comes After

Is pregnancy a contraindication to GLP-1 drugs?

No. The contraindications in the Wegovy and Foundayo labels are a personal or family history of medullary thyroid carcinoma or MEN 2, and a prior serious hypersensitivity reaction [1][2]. Pregnancy is handled in the warnings and specific-populations sections [1][2].

The Wegovy label says weight loss offers no benefit to a pregnant patient and may cause fetal harm, and it says to discontinue Wegovy when pregnancy is recognized in patients using it for weight reduction or cardiovascular risk reduction; for patients with MASH, it says to use Wegovy during pregnancy only if the potential benefit justifies the potential risk to the fetus [1]. The Foundayo label says weight loss offers no benefit in pregnancy and may cause fetal harm, and says to discontinue when pregnancy is recognized [2]. The Zepbound label advises stopping when pregnancy is recognized [3].

The human data are thin. The Wegovy label states that pharmacovigilance data and clinical trial data in pregnant patients are insufficient to establish a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes [1]. For context, the label gives the U.S. general-population background risk as 2% to 4% for major birth defects and 15% to 20% for miscarriage [1].

When to stop before a planned pregnancy

The Wegovy label gives a pre-conception window: discontinue at least 2 months before a planned pregnancy because of the long half-life of semaglutide, which is about 1 week [1]. The Zepbound and Foundayo labels give the recognition point rather than a planned-pregnancy window: discontinue when pregnancy is recognized [3][2].

The Wegovy label also lists a pregnancy exposure registry for people exposed during pregnancy: Novo Nordisk, 1-877-390-2760 or www.wegovypregnancyregistry.com [1]. The Foundayo label lists Eli Lilly at 1-800-LillyRx [2].

Do GLP-1 drugs make birth control pills less effective?

It depends on the drug. The tirzepatide label advises switching to a non-oral contraceptive method or adding a barrier method for 4 weeks after starting and after each dose increase [3]. The Foundayo label gives the same advice for 30 days after starting and after each dose increase [2].

Semaglutide labels carry no such instruction. A semaglutide tablet interaction study found no clinically significant change in ethinyl estradiol or levonorgestrel exposure [1].

The labels also note that GLP-1 drugs delay gastric emptying and can affect absorption of oral medicines [1][2].

What the animal and human evidence shows

In pregnant rats, semaglutide caused embryofetal mortality, structural abnormalities and alterations to growth at clinically relevant maternal exposures at the maximum recommended human dose [1]. In pregnant rabbits and monkeys, semaglutide caused early pregnancy losses and structural abnormalities at clinically relevant exposures, and these findings coincided with marked maternal weight loss [1].

The Foundayo label states that orforglipron is not pharmacologically active in rats and rabbits and that, based on animal reproduction studies, there may be risks to the fetus from exposure during pregnancy [2].

The Foundayo label states there are no adequate and well-controlled studies of Foundayo during pregnancy [2], and the Wegovy label says the available human data are insufficient to establish a drug-associated risk [1].

What comes after delivery

The Wegovy label states that breastfeeding is not recommended during treatment with Wegovy tablets [1].

On weight after stopping, in STEP 4, 803 adults who reached the 2.4 mg semaglutide dose after a 20-week run-in were assigned to continue semaglutide or switch to placebo for 48 weeks. The continued group lost another 7.9% of body weight; the placebo group regained 6.9%, a difference of 14.8 percentage points [4].