Lower antimüllerian hormone is associated with lower oocyte yield but not live-birth rate among women with obesity.

ABSTRACT

BACKGROUND: Antimüllerian hormone is produced by small antral follicles and reflects ovarian reserve. Obesity is associated with lower serum antimüllerian hormone, but it is unclear whether lower levels of antimüllerian hormone in women with obesity reflect lower ovarian reserve. OBJECTIVE: To determine whether lower antimüllerian hormone in women with obesity undergoing in vitro fertilization is associated with oocyte yield and live-birth rate. MATERIALS AND METHODS: Retrospective cohort from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System database of 13,316 women with obesity and 16,579 women with normal body mass index undergoing their first autologous in vitro fertilization with fresh transfers between 2012 and 2014. Normal body mass index was defined as body mass index 18.5-24.9 kg/m2, and obesity was defined as body mass index ≥30 kg/m2. Subjects with obesity were stratified as those with class 1 obesity (body mass index, 30.0-34.9 kg/m2), class 2 obesity (body mass index, 35.0-39.9 kg/m2), and class 3 obesity (body mass index, ≥40 kg/m2) based on the World Health Organization body mass index guidelines. Antimüllerian hormone levels were stratified as normal (>1.1 ng/mL), low (0.16-1-1 ng/mL), and undetectable (≤0.16 ng/mL). Multivariable modeling was used to assess oocyte yield using linear regression with a logarithmic transformation and odds of live birth using logistic regression. RESULTS: Women with obesity were older (36.0 ± 4.8 vs 35.5 ± 4.8, P < .001), had lower antimüllerian hormone (1.8 ± 2.0 ng/mL vs 2.1 ± 2.0 ng/mL, P < .001), and had fewer oocytes retrieved (11.9 ± 7.3 vs 12.8 ± 7.7, P < .001) than women with normal body mass index. Lower oocyte yield was observed among women with obesity and normal antimüllerian hormone levels compared to women with normal body mass index and normal antimüllerian hormone levels (13.6 ± 7.3 vs 15.8 ± 8.1, P < .001). No difference in oocyte yield was observed among women with obesity and low antimüllerian hormone levels (P = .58) and undetectabl antimüllerian hormone (P = .11) compared to women with normal BMI and similar antimüllerian hormone levels. Among women with a body mass index ≥30 kg/m2, antimüllerian hormone levels were associated with the number of oocytes retrieved (ß = 0.069; standard error, 0.005; P < .001) but not live-birth rate (odds ratio, 0.98; 95% confidence interval, 0.93-1.04, P = .57). CONCLUSION: Lower antimüllerian hormone in infertile women with obesity appears to reflect lower ovarian reserve, as antimüllerian hormone is associated with lower oocyte yield. Despite lower oocyte yield, lower antimüllerian hormone was not associated with lower live-birth rate among women with obesity.