Starting a medication like Wegovy often brings up questions, and if you are also using contraception, it’s completely natural to wonder whether the two might affect each other.
The good news is that, unlike some other GLP-1 medications, Wegovy does not reduce the effectiveness of oral contraceptives.
Still, it’s important to know how side effects such as vomiting or diarrhoea could impact pill absorption, and which contraceptive options are unaffected. Here we’ll guide you through what’s known and how to stay protected.
How does Wegovy work?
Wegovy is a once-weekly injection containing semaglutide. Semaglutide works by mimicking a hormone called glucagon-like peptide-1 (GLP-1). This hormone is made naturally in the small intestine and gets released in our gut after eating, sending a signal to the brain, regulating your appetite and making you feel full. It supports weight loss and blood glucose control by:
- Increasing insulin release when blood glucose is high
- Regulating your appetite and helping you feel fuller for longer
- Slowing the movement of food from your stomach into your intestines (delayed gastric emptying)
It’s this slowing of digestion that can sometimes raise questions about how oral medicines are absorbed. However, studies have shown that Wegovy does not significantly affect the absorption of the pill.
Does Wegovy affect contraception?
Wegovy does not make the pill less effective. You can continue to use:
- The combined oral contraceptive pill
- The progestogen-only pill
without needing additional precautions when starting Wegovy or increasing your dose.
That said, stomach-related side effects are common with Wegovy, especially in the first few weeks of treatment or during dose increases. This includes nausea, vomiting, and diarrhoea. These symptoms can affect how well your pill is absorbed.
Vomiting or diarrhoea whilst taking the oral contraceptive and Wegovy?
If you vomit within three to four hours of taking your oral contraceptive, or have severe diarrhoea, your pill may not be fully absorbed.
In this situation:
- Follow the “missed pill” instructions that come with your pill pack
- Use a backup method (such as condoms) until you’re sure you’re protected again (usually one week after symptoms settle)
- If diarrhoea lasts longer than 24 hours, keep taking your pill as normal but use condoms until you’ve been symptom-free for a week
- Reach out to a healthcare professional if you’re unsure
Which contraceptives are not affected by Wegovy?
The following methods are not impacted by stomach side effects or delayed digestion:
- Contraceptive implant
- Intrauterine device (IUD or coil)
- Contraceptive injection
- Contraceptive patch
- Vaginal ring
- Condoms and other barrier methods
What happens if I accidentally get pregnant whilst taking Wegovy?
Wegovy should not be used during pregnancy, as it may be harmful to a developing baby. That’s why using reliable contraception throughout treatment is strongly recommended.
- If you become pregnant while taking Wegovy, stop the medication and contact your prescriber straight away
- If you’re planning a pregnancy, let your healthcare provider know in advance, as you’ll need to stop Wegovy at least 2 months before trying to conceive (due to how long the drug stays in your body)
Key takeaway
If you’re taking Wegovy and using contraception, here’s what to remember:
- Wegovy does not reduce the effectiveness of the pill
- Nausea, vomiting, or diarrhoea can still affect pill absorption - follow “missed pill” advice and use condoms if needed
- Non-oral contraceptives (like the implant, injection, coil, or patch) are unaffected and may provide extra reassurance
- Avoid pregnancy while on Wegovy — always speak to your prescriber if you think you may be pregnant or are planning a pregnancy
References
- Bækdal, T.A., Breitschaft, A., Jacobsen, J.B., Thomsen, M. and Jensen, C.B., 2015. Semaglutide, a once-weekly human GLP-1 analog, does not reduce the bioavailability of the combined oral contraceptive, ethinylestradiol/levonorgestrel. Journal of Clinical Pharmacology, 55(5), pp.497–504. Available at: https://doi.org/10.1002/jcph.443
- European Medicines Agency (EMA), 2024. Wegovy – Summary of Product Characteristics (SmPC). Available at: https://www.ema.europa.eu/en/documents/product-information/wegovy-epar-product-information_en.pdf
- U.S. Food and Drug Administration (FDA), 2023. Wegovy (semaglutide) injection, for subcutaneous use – Prescribing Information. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/215256s007lbl.pdf
- Faculty of Sexual and Reproductive Healthcare (FSRH), 2025. Patient Information: GLP-1 agonists and contraception. Available at: https://www.cosrh.org/Common/Uploaded%20files/documents/Patient-information-GLP-1-agonists-and-contraception.pdf
- Faculty of Sexual and Reproductive Healthcare (FSRH), 2025. CEU Statement: GLP-1 agonists and contraception. Available at: https://www.cosrh.org/Common/Uploaded%20files/documents/CEU-statement-GLP-1-agonists-and-contraception.pdf
