Wegovy and the contraceptive pill: what changes, what doesn't

You've read that weight-loss injections affect the pill, here's where semaglutide is different

The concern you've probably seen shared online usually refers to tirzepatide (Mounjaro), not semaglutide. The NHS England guidance on weight-management injections is clear: there is no equivalent evidence that semaglutide reduces absorption of the oral contraceptive pill in the same way. Tirzepatide slows gastric emptying enough that oral contraceptive absorption may be reduced, especially in the first four weeks of treatment and after each dose increase, which is why women on the pill are advised to add a non-oral method during those windows. Semaglutide also slows gastric emptying, but the clinical evidence has not produced the same specific absorption warning for oral contraceptives. Our semaglutide and contraceptive pill page sets out the pharmacological reasoning in more detail. The short version: if you are switching to Wegovy from Mounjaro, or comparing the two medicines, the contraception picture is genuinely different between them. Your prescriber will know which warnings apply to which medicine.

A question our prescribers hear most weeks is whether women need to switch to a different form of contraception before starting Wegovy. The answer, based on current guidance, is usually no, but the full assessment matters, and individual circumstances vary.

What the nausea risk actually means for pill users

There is a practical consideration that does apply to everyone taking the combined or progestogen-only pill alongside Wegovy: gastrointestinal side effects. Nausea is the most commonly reported side effect of semaglutide, occurring most often in the early weeks of treatment and after dose increases. Vomiting matters here because a vomited pill may not have been absorbed. The NHS medicines page for semaglutide advises following standard missed-pill rules if you vomit within two hours of taking any oral medicine. For combined pills, that typically means using condoms for the next seven days; progestogen-only pills have their own timing rules. Check your pill's Patient Information Leaflet for the exact guidance, because it varies by brand and formulation. The important thing is that this is a general risk of vomiting, not a drug interaction specific to semaglutide, it would apply if you had a stomach bug too. Still, it's worth flagging to your prescriber and being prepared with a back-up plan for rough days. Oral semaglutide tablets and the weekly injection have the same GI profile in broad terms, though the tablet is taken first thing in the morning before food, which may affect when side effects appear during the day.

Pregnancy, trying to conceive, and when to stop

Wegovy is not licensed for use in pregnancy, and Novo Nordisk does not recommend it during breastfeeding. For anyone who is trying to conceive, the guidance is equally clear: treatment should be stopped before attempting pregnancy. The MHRA advises using effective contraception throughout treatment and for a wash-out period afterwards before trying to conceive, your prescriber or GP will advise on the specific timing based on the medicine and your situation. This means that if you are on Wegovy and your contraception plans change, the right move is to contact your prescriber before stopping contraception, not after. The oral semaglutide option carries the same pregnancy and conception restrictions. None of these medicines are suitable for under-18s. The interaction between weight-loss treatment, fertility planning and contraception is genuinely individual, and a prescriber who knows your medical history is the right person to guide it, not a forum thread. Our clinical team reviews these questions as a standard part of every consultation.

How the prescribing process handles your contraception at nume

When you complete a consultation with nume, your prescriber reads your answers personally, including which other medicines you take. Oral contraceptives are a standard part of that medicines review, and the prescriber will flag any concern before treatment is approved. If you are on the pill and have any uncertainty about whether your contraception needs adjusting, raise it clearly in the consultation notes; our prescribers are used to working through this with patients. For ongoing questions or if something changes mid-treatment, our aftercare team is available seven days a week, reach us through the contact page. You can read more about how the treatment process works on our weight loss treatments page, and if you want a broader sense of what weight-loss treatment looks like at nume, the weight loss overview covers the full landscape. Wegovy pill pricing and other practical information are available there too. Worth knowing: the FAQs page covers the questions patients ask most often about starting treatment.