Is ovarian reserve associated with body mass index and obesity in reproductive aged women? A meta-analysis.

OBJECTIVE: The associations of body mass index (BMI) and obesity with ovarian reserve are controversial. This systematic review and meta-analysis was conducted to investigate the associations in reproductive-aged women.

METHODS: PubMed and Scopus were searched up to December, 2016. Original studies on the association of BMI with ovarian reserve markers, anti-Mullerian hormone (AMH), follicle-stimulating hormone (FSH), inhibin β, and antral follicle count (AFC), either according to BMI categories or a continuous variable, were selected. Analyses were stratified into three groups based on polycystic ovary syndrome (PCOS) and fertility status of women.

RESULTS: Of 4,055 records identified, 45 studies were eligible for inclusion. Comparing the obese with nonobese, the pooled mean differences (MDs) and 95% confidence intervals (CIs) were -1.08 (95% CIs -1.52, -0.63) ng/mL for AMH, -0.22 (95% CIs -0.39, -0.06) mIU/mL for FSH, -0.09 (95% CIs -0.60, 0.42) for AFC, and -21.06 (95% CIs -41.18, -0.85) pg/mL for inhibin β in overall populations. The MDs were significant for AMH in fertile non-PCOS and PCOS women, and for FSH only in PCOS women. Fisher's Z showed significant correlations of BMI with AMH in the overall populations (-0.15 [95% CIs -0.20, -0.11]) and in all subgroups, and with FSH in the fertile non-PCOS women (-0.16 [95% CIs -0.28, -0.04]).

CONCLUSION: Ovarian reserve markers of AMH and FSH are significantly lower in obese than in nonobese women, and BMI is negatively correlated with AMH in all study populations, and with FSH in fertile non-PCOS subgroups. PCOS and fertility status do not appear to affect the associations.