GLP-1 Medicines and Women’s health
This page contains important information that women need to know about GLP-1 medicines (known as GLP-1 Receptor agonists) and how they impact contraception, HRT, pregnancy and breastfeeding.
What are GLP-1s?
GLP-1 medicines are increasingly being used to treat type 2 diabetes and to help with weight management.
You may know them by the drug name or brand name:
| GLP-1 Receptor Agonist | Brand Name Examples |
| Tirzepatide
| Mounjaro® |
| Semaglutide | Wegovy®, Ozempic® and Rybelsus®
|
| Dulaglutide | Trulicity®
|
| Exenatide | Byetta®, Bydureon BCise
|
| Liraglutide | Saxenda® , Victoza® and Diavic
|
| Lixisenatide | Lyxumia®, Suliqua
|
They can be taken by injection or in tablet form. They may be prescribed by the NHS or by a private provider.
These medicines affect how quickly food and medicines leave your stomach. They can also cause diarrhoea and vomiting. This is important for some medicines taken by mouth, including certain contraceptives and HRT, because they could affect how much of the medicine is absorbed.
GLP-1 medicines and HRT
HRT can be taken by most women while taking a GLP-1 medicine, but your HRT may need to be reviewed.
GLP-1 medicines can affect how well oral HRT is absorbed. If you take any part of your HRT by mouth this could cause a problem. Therefore we recommend anyone taking oral oestrogen or progesterone as part of their HRT seeks a review by a GP.
Oestrogen
Changes in absorption of oral oestrogen could mean your menopausal symptoms are less well controlled. It could also lead to irregular bleeding.
Transdermal oestrogen is absorbed through the skin and therefore does not depend on absorption through the stomach. The British Menopause Society recommends the transdermal route in women using GLP-1 medicines.
Progesterone
The oestrogen part of HRT can lead to thickening of the lining of the womb (endometrium), if not given together with progesterone. This can lead to heavy, abnormal bleeding or even endometrial cancer.
Progesterone is therefore an essential part of HRT if you have a womb, as it protects the womb lining.
Examples or oral progesterones include micronized progesterone (Utrogestan®), medroxyprogesterone and norethisterone.
If you take progesterone by mouth whilst taking a GLP-1, there is a risk you will not absorb it and this could lead to abnormalities of the womb.
If you use a transdermal or vaginal progesterone or a levonorgestrel intrauterine device (e.g. mirena), this is not affected by GLP-1 medicines.
If you are taking an oral progesterone and are taking a GLP-1 medicine, please arrange an HRT review with your GP.
What about bleeding?
Tell your healthcare professional if you develop new or unexpected vaginal bleeding while taking HRT and a GLP-1 medicine.
This could include:
- bleeding after you have gone through menopause
- new spotting or bleeding between expected withdrawal bleeds
- bleeding after sex
- a change in your usual bleeding pattern
- heavier or prolonged bleeding.
GLP-1 medicines and Contraception
You should not become pregnant whilst taking GLP-1 medicines. If you could become pregnant, it is recommended you use an effective method of contraception whilst taking a GLP-1 medication.
If you take the contraceptive pill and use Mounjaro® (tirzepatide)
Tirzepatide can reduce the amount of contraceptive hormone absorbed from an oral contraceptive and stop it from working. This includes the combined pill or the progesterone only pill.
If you use an oral contraceptive pill, you should consider switching to a contraceptive method that is not taken by mouth.
Alternatively you should use condoms or another barrier method as well as your pill for 4 weeks after starting tirzepatide and for 4 weeks after every dose increase.
What if I take another GLP-1?
There is no current proof other GLP-1s reduce the effectiveness of the combined pill or the progestogen-only pill.
However, vomiting or severe diarrhoea can reduce the effectiveness of any oral contraceptive, regardless of which GLP-1 medicine you are taking.
If you switch to Tirzepatide (Mounjaro® ) your contraceptive may not work (see above).
What if I have vomiting or diarrhoea?
Vomiting and diarrhoea are common side effects of GLP-1 medicines.
If you take the contraceptive pill:
- if you vomit within 3 hours of taking your pill, follow the advice for a missed pill
- if you have severe diarrhoea lasting more than 24 hours, follow the missed-pill guidance
-Link for missed pill guidance: Forgot Your Pill? Use Our Missed Pill Calculator | The Lowdown
- if vomiting or diarrhoea continues, use condoms and consider discussing a non-oral contraceptive method with a healthcare professional.
What about non-oral methods of contraception?
Non oral methods such at the coil, implant, injection, patch or ring are not affected by GLP-1s, so are safe to use without taking extra precautions.
Emergency contraception
If you need emergency contraception while taking a GLP-1 medicine, tell the healthcare professional providing your care that you are taking a GLP-1 medicine.
There is currently limited evidence about whether GLP-1 medicines affect the absorption or effectiveness of oral emergency contraception.
A copper IUD is the most effective form of emergency contraception and is not dependent on oral absorption or affected by vomiting or diarrhoea.
Your healthcare professional can advise you about the most appropriate option based on your circumstances.
GLP-1 medicines and pregnancy
Can I take a GLP-1 medicine during pregnancy?
No. GLP-1 medicines should not be taken during pregnancy or whilst trying to conceive.
There is not enough safety information to establish whether these medicines are safe for an unborn baby.
If you think you may be pregnant while taking a GLP-1 medicine, contact your GP, prescriber or other healthcare professional as soon as possible.
How long should I stop a GLP-1 medicine before trying to become pregnant?
The medicine needs to be stopped sufficiently early to allow it to leave your body. This is called a ‘washout period’
CoSRH guidance gives the following advice:
| GLP-1 Agonist | Washout Period
|
| Tirzepatide | 1 month
|
| Semaglutide | 2 months
|
| Exenatide | 12 weeks
|
If you are planning a pregnancy
It is a good idea to speak to your healthcare professional before stopping contraception or attempting to conceive.
You can discuss:
- when to stop your GLP-1 medicine
- alternative treatment for diabetes or weight management if required
- your current contraception
- folic acid and other pre-pregnancy care
- any other medicines you are taking.
Can I take a GLP-1 medicine while breastfeeding?
Current guidance says that GLP-1 medicines should not be taken while breastfeeding.
There is currently insufficient safety information to know whether these medicines could harm a breastfed baby.
If you are breastfeeding and have been prescribed or are considering a GLP-1 medicine, speak to your GP, prescriber or another healthcare professional.
Important information
It is particularly important that the healthcare professionals managing your GLP-1 treatment and your HRT/contraception know about each other's prescriptions. Please inform us if you are taking a GLP-1 medication so we provide appropriate, safe care.
We advise you do not change the dose of your GLP-1 medicine, HRT, progesterone or contraception without discussing this with your GP, prescriber or another appropriately qualified healthcare professional.
This webpage is intended to provide general information for patients. It does not replace an individual assessment by a healthcare professional. Please seek a review with your GP if you have any questions or concerns arising from this page.
GLP-1 agonists are relatively new medications and advice may change as evidence evolves.
This page has been informed by current UK guidance at the time of writing from the Coalition for Sexual and Reproductive Health (CoSRH), FSRH, British Menopause Society (BMS), Primary Care Women’s Health Society, Best Use of Medicines in Pregnancy (BUMPS) and GOV.uk