Ozempic is semaglutide, approved for type 2 diabetes, and its label is cautious about pregnancy because the human evidence is thin. What exists comes from animal studies and from pregnancies that were exposed by accident or before they were known.
This page sets out what the labels instruct, what the animal work found, and what the observational studies of exposed pregnancies measured.
What the Ozempic label says
The label states there are “limited data” on semaglutide in pregnant women [1]. It says Ozempic should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus.
Its instruction for planning is specific: stop at least 2 months before a planned pregnancy “due to the long washout period for semaglutide.” Semaglutide is dosed once weekly because it clears slowly, as set out in semaglutide dosage.
The label also weighs the other side. Poorly controlled diabetes in pregnancy raises the risk of birth defects, stillbirth and pre-eclampsia, so stopping a diabetes drug has its own consequences.
It gives the background rates too. In the general U.S. population, major birth defects affect 2% to 4% of recognized pregnancies and miscarriage 15% to 20%.
The weight-loss label is firmer
Wegovy is the same molecule, labeled for weight. Its label states that “weight loss offers no benefit to a pregnant patient and may cause fetal harm” [2].
It says to discontinue Wegovy used for weight reduction once a pregnancy is recognized, and to stop at least 2 months before a planned one. A pregnancy exposure registry tracks outcomes in women exposed to it.
What the animal studies found
In pregnant rats, semaglutide during organogenesis caused embryofetal deaths, structural abnormalities and altered growth at exposures comparable to the maximum human dose [2].
Rabbits and cynomolgus monkeys showed early pregnancy losses and structural abnormalities at clinically relevant exposures. In both species these findings coincided with marked weight loss in the mothers.
That last point matters for reading them. The label does not say whether the harm came from the drug itself or from the mothers eating less and losing weight.
What studies of exposed pregnancies found
No randomized trial has given semaglutide to pregnant women. The human evidence comes from registries and insurance records of pregnancies that were exposed early, and each study has limits.
| Study | Who was studied | Main result |
|---|---|---|
| Nordic, US and Israeli health records | 938 infants exposed to a GLP-1 drug, mothers with type 2 diabetes | Major malformations 8.3%; risk ratio 0.95 versus insulin (95% CI 0.72 to 1.26) |
| Six teratology services | 168 exposed pregnancies, for diabetes or obesity | Major birth defects 2.6%, against 2.3% (diabetes) and 3.9% (obesity) comparison groups |
| US claims, continuing versus stopping | 3,572 pregnancies with a GLP-1 drug filled before conception | Non-live birth 29.7% versus 27.1% (risk ratio 1.09, 95% CI 0.98 to 1.23) |
The multinational study compared infants of mothers with type 2 diabetes, so its 8.3% malformation rate sits beside 7.8% for infants exposed to insulin [3]. The authors said the results did not suggest a large added risk, while calling some estimates imprecise.
The teratology study was small, 168 exposed pregnancies [4]. Its authors described it as reassuring for inadvertent first-trimester exposure and called for larger studies.
The claims study asked a sharper question: what happens if a woman keeps filling a GLP-1 drug into the first trimester [5]? Its malformation estimate, a prevalence ratio of 1.21 (95% CI 0.83 to 1.82), was compatible with no added risk and with a clinically relevant one.
Breastfeeding
The Ozempic label reports no data on semaglutide in human milk [1]. In rats it reached milk at 3 to 12 times lower than in the mother’s blood.
The Wegovy label treats the tablets differently [2]. Their absorption enhancer and its metabolites appear in human milk, so it says breastfeeding is not recommended on the tablets.
Birth control on semaglutide
The Ozempic label reports that its pharmacology studies, which included an oral contraceptive, found no clinically relevant effect on absorption [1]. Neither semaglutide label adds a contraception instruction.
Tirzepatide differs here. The Zepbound label advises switching from the pill, or adding a barrier method, for 4 weeks after starting and after each dose increase [7]. That is covered in tirzepatide side effects.
What is still unknown
No study here measured semaglutide alone in pregnancy with enough women to settle rare outcomes. Most grouped several GLP-1 drugs together, and the largest study included only mothers with type 2 diabetes.
What happens to weight after stopping before a pregnancy is set out in what happens when you stop taking semaglutide. The drug’s broader record is in semaglutide side effects and how much weight you can lose on semaglutide.
To match a goal to options, the goal finder and the weight-loss peptide rankings set them side by side.