Exploring the Link Between Mounjaro and Fertility
This is an expert update from Professor Gerard Conway on how Mounjaro may impact fertility in women with polycystic ovary syndrome (PCOS), including potential benefits and medical considerations. It highlights emerging evidence, metabolic mechanisms, and clinical considerations relevant to reproductive endocrinology.
Metabolic Effects of GLP-1 Agonists in PCOS
Mounjaro is a member of the family of GLP-1 agonist injections, which are primarily used for type 2 diabetes and weight loss, but they may indirectly improve fertility, especially in women with polycystic ovary syndrome (PCOS).
This is mostly ascribed to their function in diminishing insulin resistance, a significant contributor to hyperandrogenism and anovulation in people with PCOS.
What Are the Potential Fertility Benefits of Mounjaro for Women With PCOS?
Many women with PCOS have insulin resistance, which leads to higher testosterone levels and more irregular periods. With longer gaps between periods, ovulation is impaired, so the chances of conceiving are reduced.
Mounjaro-induced weight loss (typically 5-15% of body weight) may improve insulin sensitivity, decrease androgen levels, and restore ovulatory cycles, enhancing chances of conception.
Clinical Questions and Evidence-Based Insights
Can Mounjaro Improve Ovarian Function?
Emerging Research in animals suggests GLP-1 receptors are present in ovarian tissue, and GLP-1 agonists may reduce ovarian inflammation and improve follicle development.
Can Mounjaro Improve Fertility Treatment Outcomes?
Women with PCOS who lose weight via GLP-1 agonists or other methods often have a higher success rate with all fertility treatments, including clomiphene, letrozole, or IVF.
Can Mounjaro Help Improve Fertility in Women Without PCOS?
There is increasing evidence that women who are overweight have reduced egg quality, meaning that the eggs do not fertilize readily. Weight loss may therefore improve egg quality.
IVF success rates tend to be higher in women with a healthy or average body weight. Therefore, a course of treatment to reduce weight before starting IVF is often recommended, and Mounjaro is one of the most effective ways of achieving such an outcome if time allows.
Important Considerations Before Using Mounjaro for Fertility Support
Mounjaro is NOT an approved fertility drug. Unlike metformin, which also improves insulin sensitivity, GLP-1 agonists are not yet approved for PCOS or for fertility.
There is a complete lack of safety data for GLP-1 agonists in pregnancy. Current guidelines recommend stopping injections for at least 3 months before conception and using contraception while on injections.
Some studies suggest combination treatment of metformin + GLP-1 agonists together may be more effective for PCOS than either alone.
Summary
GLP-1 receptor agonists, including Mounjaro, may indirectly support fertility in PCOS by promoting weight loss, reducing insulin resistance, and lowering testosterone. However, they should be used under medical supervision and discontinued for 3 months before trying to conceive.
Optimal fertility outcomes require a comprehensive approach that includes lifestyle modifications (diet and exercise), pharmacotherapy (e.g., metformin), and potential ovulation induction – all of which should be coordinated with GLP-1 agonist use and tailored to the individual patient profile.
Professor Gerard Conway is a senior Consultant Endocrinologist and Medical Director of the London Lauriston Clinic.
