What is the effect of Mounjaro (tirzepatide) on female contraception?

From the FDA Drug Label

Use of MOUNJARO may reduce the efficacy of oral hormonal contraceptives due to delayed gastric emptying. This delay is largest after the first dose and diminishes over time Advise patients using oral hormonal contraceptives to switch to a non-oral contraceptive method, or add a barrier method of contraception for 4 weeks after initiation and for 4 weeks after each dose escalation with MOUNJARO [see Drug Interactions (7.2) and Clinical Pharmacology (12.2,12.3)].

Mounjaro may reduce the efficacy of oral hormonal contraceptives in women due to delayed gastric emptying.

• Patients using oral hormonal contraceptives should be advised to:
  • Switch to a non-oral contraceptive method
  • Add a barrier method of contraception for 4 weeks after initiation and for 4 weeks after each dose escalation with Mounjaro 1 1 1

From the Research

Mounjaro (tirzepatide) may reduce the effectiveness of oral contraceptives due to its effect on delaying gastric emptying, which can impact the absorption of oral medications including birth control pills, as shown in a recent study published in 2024 2. This is particularly important during the initial weeks of Mounjaro treatment or after dose increases when gastrointestinal effects are most pronounced. The medication's impact on slowing stomach emptying means that oral contraceptives may not be absorbed properly or at the expected rate, potentially reducing their effectiveness at preventing pregnancy. Some key points to consider include:

• Women taking Mounjaro should consider using additional contraceptive methods or switching to non-oral forms of birth control such as IUDs, implants, injections, or barrier methods.
• If continuing with oral contraceptives while on Mounjaro, women should take their birth control pills consistently and consider taking them at a time separated from Mounjaro administration.
• It's essential to discuss contraceptive options with a healthcare provider when starting Mounjaro to ensure adequate pregnancy prevention, as also mentioned in other studies 3, 4, 5, 6. However, the most recent and highest quality study on this topic is the one published in 2024 2, which provides the most relevant information for guiding clinical decision-making.