Relation between body mass index (BMI) and ovarian reserve: a cross-sectional study

Abstract

Objective. To investigate whether body mass index (BMI) ≥25 kg/m2 is associated with diminished ovarian reserve (DOR) in women undergoing fertility assessment at an assisted reproduction center. Patients and methods. An analytical cross-sectional study was conducted between January 2015 and October 2021. A total of 138 eligible women were included. Ovarian reserve was assessed using anti-Müllerian hormone (AMH) and/or antral follicle count (AFC) based on POSEIDON criteria. Exclusion criteria comprised BMI <18.5 kg/m2, polycystic ovary syndrome, previous pelvic surgery, metabolic or cardiovascular disease, malignancy, diabetes mellitus, and history of chemotherapy or radiotherapy. Odds ratios (OR) with 95% confidence intervals (CI) were estimated using chi-square tests and multivariable logistic regression. Results. In the analyzed cohort, over half of the participants presented BMI ≥25 kg/m2, and 56.5% exhibited DOR. The prevalence of DOR was notably higher among women with BMI ≥25 kg/m2 (64.9%) compared with those with BMI <25 kg/m2 (45.9%). BMI ≥25 kg/m2 was significantly associated with DOR (OR = 2.28; 95% CI: 1.05–4.97; p = 0.038), while age ≥40 years showed the strongest association (OR = 3.73; 95% CI: 1.62–8.59; p = 0.002). No significant associations were observed for marital status or place of residence. Conclusions. BMI ≥25 kg/m2 is factor independently associated with DOR. These findings reinforce the need to incorporate BMI-based risk assessment and weight management strategies into fertility evaluation and clinical decision-making for women of reproductive age. Key words: body mass index, ovarian reserve, аnti-Müllerian hormone, polycystic ovary syndrome, obesity