Mounjaro and Wegovy injections contain the active ingredients tirzepatide and semaglutide respectively. These are from the class of medicines known as GLP-1 agonists and are currently licensed for diabetes and/or weight loss.
Using these injections may affect how well progesterone is absorbed when taken by mouth (orally), this will mainly implicate oral contraception and hormone replacement therapy (HRT).
At Five Valleys Medical Practice, we do not currently prescribe GLP-1 agonists for weight loss, but some of our patients choose to have these medications prescribed by private providers.
Whilst it is the private provider’s responsibility to ensure patients are aware of the risks and benefits associated with the medication they prescribe, we want to give the following advice to our patients.
If you take the oral Contraceptive Pill (i.e. the combined pill, or the progestogen only pill/”mini pill”) and MOUNJARO
The progesterone component of the pill may not be absorbed adequately when using Mounjaro injections, reducing how well it works at preventing pregnancy.
No contraception methods are 100% reliable, but the following advice has been given by the Faculty of Sexual and Reproductive Healthcare.
If you are using Mounjaro you should use a barrier method of contraception (e.g. condoms) in addition to your pill for four weeks after starting the medication, and for four weeks after any increase in dose.
Alternatively, you may wish to consider another (non-oral) method of contraception whilst using Mounjaro.
There is currently no evidence that other weight loss injections including semaglutide (Wegovy) reduce the effectiveness of oral contraception.
Diarrhoea and vomiting are common side effects of this class of medication, and this can reduce the effectiveness of the pill. If vomiting occurs within three hours of taking the contraceptive pill, or severe diarrhoea occurs for more than 24 hours, you should follow the guidance for missed pills. You should consider an alternative non-oral method of contraception or the addition of condoms if diarrhoea or vomiting persists.
More information is available on this link: GLP-1 agonists and Contraception
If you are using oral progesterone (e.g. Utrogestan, micronized progesterone, Gepretix, medroxyprogesterone, norethisterone) as part of your Hormone Replacement Therapy (HRT) and MOUNJARO or WEGOVY
The oral progesterone may not be absorbed adequately when using Mounjaro or Wegovy injections, which may increase your risk of harmful thickening of your womb lining.
Guidance has been released by the British Menopause Society with some recommendations to help mitigate this risk.
The options they suggest are:
- Switching from oral progesterone to the progesterone releasing IUD (coil), e.g. Mirena
- Switching from oral progesterone to a combination progesterone/oestrogen releasing patch (this will also mean a change to your oestrogen product)
- Increasing the dose of oral progesterone. Though they have suggested doses to use, there is some uncertainty about this, and a non-oral progesterone product is preferred.
The option chosen needs to be a joint decision between you and your prescriber, after careful discussion about the pros and cons of each option.
DO NOT make any changes to how you use your HRT products without consulting your prescriber.
Please contact the surgery via Anima if you would like to discuss this further and we haven’t already invited you to make an appointment.