If you are choosing a contraception method, or already taking one, then it is important to understand if this will be affected by GLP-1 medications.
As this is a relatively new type of medication, it is important to note that not all evidence surrounding their use has been collected. If you have any doubts or questions, please discuss these with a medical professional, like your GP.
In this blog, you will find out:
- What are GLP-1s?
- How can contraception be affected by GLP-1s?
- How can emergency contraception be affected by GLP-1s?
- Which types of contraception are not affected by GLP-1s?
- What to consider when switching from one type of GLP-1 to another when you are taking contraception.
- What to do if you become pregnant whilst taking GLP-1 medication.
1. What are ‘GLP-1s’?
GLP-1s are prescription-only medications that may be prescribed by a qualified healthcare professional for people with type two diabetes, or to facilitate weight loss.
They are often most well-known by their brand names, some of which include Mounjaro, Wegovy and Ozempic.
2. How can contraception be affected by GLP-1s?
Contraception, like the pill, can be affected by GLP-1s.
If you are taking contraceptive pill (either the combined pill or the progesterone-only pill) whilst you are on the GLP-1 called tirzepatide (Mounjaro) then you should use a barrier method of contraception (for example, condoms) for four weeks after starting to take the GLP-1 medication.
You should also use a barrier method on this type of GLP-1 following any increase in dose for four weeks. This is because tirzepatide works slightly differently to the other GLP-1 medication and can affect its absorption.
You could also consider using a different method of contraception whilst taking tirzepatide (Mounjaro). For example, you may like to choose a long-acting contraceptive, like the hormonal coil or the injection, as these types of contraception will not require any extra considerations when taking GLP-1s. Once long-acting contraceptives are fitted, you do not need to think about them again until they need replacing.
There is no evidence at the moment that other types of GLP-1 (e.g. Wegovy, Ozempic) reduce the effectiveness of any of the contraceptive pills.
However, one of the common side effects of GLP-1s can be sickness, diarrhoea and vomiting. If you experience any of these side effects whilst you are also taking the contraceptive pill, it is important that you follow guidance for missed pills. You may also need to consider a non-oral, or barrier, method of contraception if diarrhoea and vomiting continue.
3. How can emergency contraception be affected by GLP-1s?
It is not yet known if emergency contraception is affected by GLP-1s. Emergency contraception includes the non-hormonal (copper) coil and the emergency contraceptive pill. The non-hormonal coil is the most effective method of emergency contraception and is not affected by diarrhoea and vomiting.
If you are accessing emergency contraception, please let your healthcare provider know about all other medications you are taking, including GLP-1 medication.
4. What types of contraception are not affected by GLP-1s?
There is no evidence to suggest that any types of contraception not taken orally (by the mouth) would be affected by GLP-1 medication. This means that short-acting methods of contraception (like the contraceptive patch), barrier methods (like the external condom), and long-acting methods (like the hormonal coil), are not affected by GLP-1 medication.
5. What to consider when switching from one type of GLP-1 to another whilst taking contraception.
If you are changing your GLP-1 medication from tirzepatide (Mounjaro) to another type of GLP-1, like Semaglutide (Ozempic, Wegovy), whilst taking oral contraception (like the contraceptive pill) you should use a barrier method of contraception for four weeks following the switch.
You should also use a barrier method for four weeks following any increase in dose of tirzepatide.
6. What to do if you become pregnant whilst taking a GLP-1 medication.
It is very important that you use a form of contraception alongside any GLP-1 medication, as GLP-1s should not be taken in pregnancy.
If you become pregnant whilst on a GLP-1, then you should discuss this immediately with a medical professional.
If you are planning to become pregnant, then you should stop taking GLP-1 medication for a number of weeks before a planned pregnancy. For Tirzepatide (Mounjaro) you should wait one month before a planned pregnancy. For Semaglutide (Ozempic, Wegovy) you should stop for two months. For Exenatide (Bydureon BCise) you should stop for 12 weeks.
If you are accessing abortion care after becoming pregnant whilst taking a GLP-1, please notify your abortion provider.
If you have any questions or concerns about taking contraception alongside GLP-1s, then you should speak to a medical professional in the first instance. Please seek medical advice before beginning any new types of medication, including contraception. You can find lots of useful help and advice about contraception here.
Other resources
College of Sexual and Reproductive Healthcare – GLP agonists and contraception information booklet
GOV.UK – GLP-1 medicines for weight loss and diabetes: what you need to know
