In short
Overview
Mounjaro is not used in pregnancy and changes how well the pill works in some women. This page sets out the rules.
Direct Answer
Mounjaro (tirzepatide) is not used in pregnancy and is stopped at least 1 month before a planned pregnancy, because it stays in the body for a long time, according to the product information (Mounjaro SmPC).
Women on the contraceptive pill switch to a non-oral method or add a barrier method for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase, because the effect of the pill in women with overweight is not certain.
Who This Applies To
- Women on Mounjaro using the pill.
- Women planning a pregnancy.
- Women who think they are pregnant on Mounjaro.
- Women who are breastfeeding.
Option Comparison / Decision Criteria
What are the contraception and pregnancy rules on Mounjaro?
The rules on Mounjaro depend on the situation.
| Situation | Rule |
|---|---|
| Starting Mounjaro on the pill | Non-oral method or added barrier for 4 weeks |
| Each dose increase on the pill | Non-oral method or added barrier for 4 weeks |
| Planned pregnancy | Mounjaro stopped at least 1 month before |
| Pregnancy | Mounjaro not used |
| Breastfeeding | Mounjaro not used; treatment starts after breastfeeding |
Why an In-Person Physician Review Matters
Why does Mounjaro affect the pill?
Mounjaro affects the pill because it slows stomach emptying, which lowered peak hormone levels of a combined pill by more than half after one dose. Overall exposure fell by about a fifth. The data in women with overweight are limited, so a non-oral method or barrier protection covers the uncertain weeks.
Frequently Asked Questions
Mounjaro is stopped at least 1 month before a planned pregnancy.
Mounjaro lowers pill hormone levels, so a non-oral method or a barrier is used for 4 weeks after starting and after each dose increase.
No, Mounjaro is not used during breastfeeding.
Stop the injections and contact the prescriber straight away for advice.
Evidence
Where this information comes from
Every figure on this page is taken from the sources below. All of them are free to read, so you can check them yourself.
This page is general medical information and does not replace a personal consultation. Trial results are averages across large groups, not a prediction for any one person.