The relationship between anti‐Müllerian hormone, body mass index and weight loss: A review of the literature

Anti‐Müllerian hormone (AMH) is commonly used as a proxy for ovarian reserve due to its secretion by antral follicles. It is considered a metric for prediction of ovarian response to certain assisted reproduction therapies. As obesity has a negative impact on fertility, it is important to establish whether obesity‐induced hormonal changes influence AMH levels, if and how weight loss affects AMH, and if that influence represents altered reproductive function. The aim of this study was to review the existing literature on the effects of body mass index and weight loss on AMH levels. A PubMed literature keyword search with relevant terms was performed to identify studies that have reported on the AMH/BMI relationship in cohorts with or without polycystic ovarian syndrome (PCOS). A second search was performed to gather publications on weight loss and AMH. Both searches were filtered for all full‐text, English‐language, adult‐female and human‐only literature through 1 January 2022. The relationship between AMH and body mass index (BMI) in reproductive‐aged women remains inconclusive, with studies in women with and without PCOS producing mixed results. Research in this area is currently limited by failure to analyse the full spectrum of obesity, hindering generalization to a global population increasingly affected by the condition. Some authors pointed to evidence of race/ethnicity as a confounding factor of the relationship, but results between studies are contradictory. Limited evidence on weight loss suggests it may decrease AMH levels despite improving fertility outcomes, particularly after bariatric surgery. The impact of BMI and weight loss on AMH levels has not been conclusively established. Future studies will require appropriate design and sample size calculations, consideration for additional potential confounding factors and inclusion of higher BMIs and a thorough analysis of the full range of obesity.