Semaglutide Pregnancy Risk: What the Evidence Says and What to Do

You've just found out you're pregnant, and you're still on Wegovy

This is a question our prescribers hear most weeks, and the answer is consistent: stop semaglutide and contact your GP or midwife as soon as possible. Continuing is not recommended. The NHS medicines page for semaglutide states clearly that it should not be used during pregnancy, and the summary of product characteristics (SmPC) categorises it as contraindicated once pregnancy is confirmed.

The underlying concern comes from animal studies. In reproductive toxicology research, semaglutide was associated with adverse effects on foetal development at clinically relevant doses. There are no adequate, well-controlled studies in pregnant humans, and that absence of data is itself the problem. Regulators cannot confirm it is safe, so the advice is unambiguous: do not continue.

Stopping abruptly mid-treatment will not cause an immediate crisis, but your appetite and eating patterns may shift as the medicine clears your system. Let your obstetric team know you were taking it so they can factor that into your care. You can read more about the broader side-effect profile of Wegovy if you want context on what to expect as the medicine washes out. Semaglutide has a long half-life (roughly one week) so it takes several weeks to clear fully after the last dose.

Planning a pregnancy while on semaglutide: when to stop and what happens next

If a pregnancy is planned rather than a surprise, the situation is more straightforward, you have time to manage the transition properly. The MHRA advises using contraception while on GLP-1 medicines and for a wash-out period after stopping before trying to conceive. Your prescriber will give specific guidance on the length of that period based on your treatment history; do not rely on generic estimates you find online.

For women using oral contraceptives alongside semaglutide, there is an additional consideration. For tirzepatide (a different medicine), NHS guidance notes that pill absorption may be reduced, and an additional contraceptive method is recommended in the early weeks of treatment. Current evidence does not show the same effect for semaglutide specifically, but this is worth raising with your prescriber if you are using combined oral contraception alongside Wegovy. The NHS England weight-management injections page covers contraception considerations in this context.

Weight regain after stopping any GLP-1 medicine is a real and well-documented pattern. Your prescriber can help you think through how to protect as much of your progress as possible through dietary choices and activity during pregnancy, and when it would be appropriate to revisit medical weight management afterwards. Details of what treatment options look like once you are eligible again are covered on our treatment page.

Breastfeeding and semaglutide: the same precaution applies

The recommendation against semaglutide extends to breastfeeding. It is not known whether semaglutide passes into human breast milk, and the potential for harm to a nursing infant cannot be ruled out. Animal data showed semaglutide present in milk of lactating rats, which is the basis for caution.

This means the post-birth window (which many people assume is the safe moment to restart) is also not suitable if you are breastfeeding. The clinical advice is to wait until breastfeeding has ended before resuming weight-management treatment with semaglutide. Your GP or health visitor is the right person to discuss timing, since individual circumstances vary considerably: how long you intend to breastfeed, your BMI, any other health conditions, and the overall picture of your postnatal care.

If you are curious what the Wegovy programme involves once you are in a position to start or restart, our Wegovy treatment overview covers how the medicine works, what the titration schedule looks like in practice, and who it is licensed for. There is also a dedicated look at Wegovy's side effects in the context of pregnancy for those wanting the fuller clinical picture.

What is known, what remains uncertain, and who to speak to

To be direct about what the evidence base actually shows: there are no published randomised controlled trials of semaglutide in pregnant humans. The data gap is not because researchers have looked and found no signal, it is because studies in pregnant people are ethically and practically constrained. Animal reproductive toxicology findings raised enough concern that the medicine was kept out of pregnancy categories in licensing, and that position has not shifted.

What is known with confidence is that untreated obesity also carries risks in pregnancy, including gestational diabetes, pre-eclampsia, and complications in delivery. This is a genuinely complex clinical balance, and it is exactly the kind of nuanced conversation that belongs with a GP or specialist, not a self-managed decision. The MHRA and prescribers are clear that semaglutide is not the tool for that period, whatever the underlying need.

If you are not pregnant and not planning to be, and you want to understand the broader landscape of medically supervised weight management (eligibility, what the clinical process involves, what comes with a regulated private prescription) our clinical team page explains who reviews consultations at nume and how the oversight works. Every consultation at nume is reviewed personally by a GPhC-registered Independent Prescriber. Pregnancy history and contraception are part of that review, not an afterthought.

Questions about whether semaglutide is safe in pregnancy, about whether Wegovy is safe for pregnancy specifically, or about Wegovy's safety during pregnancy are covered in more depth in dedicated pages if you need the clinical detail laid out further.