GLP-1 medicines and pregnancy: what should you know?

Planning pregnancy: the practical step

UK MHRA advises avoiding GLP-1 medicines during pregnancy, when trying to conceive and while breastfeeding, and recommends effective contraception during treatment. How long a medicine remains in the body varies. UK MHRA guidance says to wait at least two months after stopping semaglutide and at least one month after stopping tirzepatide before trying to conceive. For liraglutide, the same guidance lists zero months and says it should be stopped just before trying to become pregnant. It advises using contraception or avoiding sex that could lead to pregnancy during the relevant waiting period as well as during treatment. These are UK, medicine-specific recommendations, not an interval for every drug. Discuss the exact product, indication and timing with the prescriber before trying to conceive.12

For people taking tirzepatide (Mounjaro) and the contraceptive pill, UK MHRA advises adding a barrier method such as condoms for four weeks after starting tirzepatide and for four weeks after each dose increase, or switching to a non-oral method. Discuss the choice and when it becomes effective with a healthcare professional. For tirzepatide and oral contraception, see the tirzepatide profile: UK, US and EU advice differs. See weight medicines and the contraceptive pill for a detailed comparison.1

What if pregnancy is unexpected?

Contact the prescriber promptly and explain the product, when it was last taken and why it was prescribed. UK pregnancy-information service BUMPS advises stopping a GLP-1 used for weight loss when pregnancy is discovered; intentional weight loss during pregnancy is not recommended. If it is used for diabetes, speak promptly to the diabetes team about changing treatment: glucose control during pregnancy matters too. Do not let fear or uncertainty prevent you from getting care. Advice depends on the medicine, health condition and country.12

What does early-pregnancy evidence show?

A 2024 observational study followed 168 pregnancies exposed to a GLP-1 receptor agonist in the first trimester and compared them with two groups of pregnancies with diabetes or overweight or obesity. The study did not find an increased rate of major birth defects in those comparisons, but the number exposed was small and the estimates were imprecise. The study does not prove that every medicine or later-pregnancy exposure is safe, or establish an individual outcome.

In September 2026, UK BUMPS described studies involving about 47,000 women, most of whom used a GLP-1 before recognising pregnancy and stopped soon afterwards. It considers the findings reassuring about accidental early exposure, while calling for further research and noting that risks from use in the second and third trimesters remain uncertain.

In the 2024 study’s primary birth-defect analysis, three of 117 eligible outcomes in the exposed group had a major birth defect, compared with three of 128 in the diabetes comparison group and five of 127 in the overweight-or-obesity comparison group. These denominators were smaller than the enrolled pregnancy groups because the analysis required information on birth defects; it excluded certain genetic, chromosomal and infection-related anomalies. With so few events, the range of plausible effects is wide. Because treatment was not randomly assigned, differences in health and other factors could also affect comparisons. These numbers are not a personal risk estimate.

Will I need an extra scan? UK BUMPS guidance says exposure to a GLP-1 medicine in early pregnancy alone does not require additional monitoring for major birth defects. It describes a detailed scan around 20 weeks as part of routine antenatal care; diabetes or other circumstances may mean more monitoring is offered. Tell your maternity team about the exposure so they can advise on your individual care.23

Breastfeeding and individual decisions

UK MHRA advises against using these medicines while breastfeeding because safety information is limited. Discuss feeding plans and treatment options with a healthcare professional; guidance and product information may differ by country. For product-specific evidence, see semaglutide and tirzepatide.12