Short answer: The Wegovy and Ozempic labels say to stop semaglutide at least 2 months before a planned pregnancy because it takes a long time to leave the body. The Wegovy and Zepbound labels say weight loss offers no benefit in pregnancy and may harm the baby, so they are stopped when a pregnancy is recognized. The Mounjaro and Zepbound labels give no stop window before pregnancy, but warn that the shots can make birth control pills work less well.
| Label | Before pregnancy | During pregnancy |
|---|---|---|
| Wegovy (semaglutide) | Stop at least 2 months before a planned pregnancy, because of semaglutide's long half-life | Stop when pregnancy is recognized if used for weight reduction |
| Ozempic (semaglutide) | Stop at least 2 months before a planned pregnancy, because of the long washout period | Use only if the potential benefit justifies the potential risk to the fetus |
| Zepbound (tirzepatide) | No stop window given; non-oral or added barrier birth control for 4 weeks after starting and after each dose step | Weight loss is not recommended; stop when pregnancy is recognized |
| Mounjaro (tirzepatide) | No stop window given; same birth control advice as Zepbound | Use only if the potential benefit justifies the potential risk to the fetus |
The split follows what each medicine is approved for. Wegovy and Zepbound are approved mainly for weight, and both labels say weight loss offers no benefit to a pregnant patient and may cause fetal harm. They add that some weight gain, based on weight before pregnancy, is recommended for every pregnant patient, including those with obesity. Ozempic and Mounjaro treat type 2 diabetes, and their labels point to the risks that poorly controlled diabetes itself carries in pregnancy. The Ozempic leaflet says to talk with your provider about the best way to control blood sugar if you plan to become pregnant.
Semaglutide has a half-life of about one week, so it takes weeks for a dose to clear. The labels tie the 2-month window to that: Wegovy says it is "to account for the long half-life of semaglutide", and Ozempic says it is due to "the long washout period". The Wegovy leaflet says you should stop Wegovy 2 months before you plan to become pregnant.
The tirzepatide labels do not set a matching window. Tirzepatide's half-life is about 5 days. The labels do not turn that into a number of weeks, so this page does not either; when to stop before trying to conceive is a question for your prescriber.
Not much in people. All four labels say the human data are not enough to judge the risk of birth defects, miscarriage or other outcomes. In animal studies, semaglutide and tirzepatide given during pregnancy led to reduced fetal growth and fetal abnormalities at exposures similar to human doses, and semaglutide also led to pregnancy losses. The labels note these effects came alongside weight loss and lower food intake in the mother animals.
For context, the labels give the background risk in US pregnancies as 2% to 4% for major birth defects and 15% to 20% for miscarriage, and higher in people with poorly controlled diabetes before pregnancy.
Wegovy and Zepbound each run a pregnancy registry that collects outcomes from people exposed during pregnancy; the leaflets give the phone numbers and say to ask your provider about taking part.
Tirzepatide slows stomach emptying most after the first dose, and the Mounjaro and Zepbound labels say this may make birth control pills less effective. They advise switching to a non-oral method, or adding a barrier method, for 4 weeks after starting and 4 weeks after each dose increase. The birth control guide covers this in detail, including how the semaglutide labels differ.
On breastfeeding, a single-dose study in the tirzepatide labels found tirzepatide in breast milk was undetectable or low, with no data on effects on the baby. The Ozempic and Wegovy injection labels say there are no data on semaglutide in human milk. The Wegovy label says breastfeeding is not recommended while taking Wegovy tablets, because of an ingredient in the tablet that may build up in infants.
If you are planning a pregnancy, a dated note of your last dose makes the timing easy to show your care team. Dose Track keeps that history.
Read more on Dose Track: Mounjaro, Zepbound and birth control · How long GLP-1 drugs stay in your system · Female fertility · PCOS · Washout period (glossary) · Half-life (glossary)