Anti-Müllerian hormone has limited ability to predict fecundability in Chinese women: a preconception cohort study.

ABSTRACT

RESEARCH QUESTION Can anti-Müllerian hormone (AMH) level predict female fecundity in healthy reproductive-aged Chinese women? DESIGN: Preconceptional couples (n = 993) attempting pregnancy without contraception provided information on serum AMH concentrations and essential covariates. They were followed up for 12 months or until a clinically recognized pregnancy occurred between August 2013 and April 2015. Fecundability was indirectly assessed by time-to-pregnancy, defined as the number of menstrual cycles taken to conceive by a sexually active couple without using birth control. Discrete-time Cox proportional hazards model was used to estimate fecundability ratios in relation to AMH levels. Potential effect modifications by woman's age, BMI and menstrual cycle irregularity were examined through stratified analyses. Restricted cubic splines were applied to model the potential non-linear relationship between AMH and fecundability. RESULTS: After adjusting for woman's age, BMI, education status, smoking status, alcohol consumption and parity, AMH level (either as a continuous or categorical variable) was not significantly associated with fecundability. Stratified analyses revealed that, compared with intermediate AMH level (2.78-6.94 ng/ml), low AMH level (<2.78 ng/ml) was associated with reduced fecundability among women with menstrual cycle irregularity; the estimate did not reach statistical significance (adjusted fecundability ratio 0.43, 95% CI 0.16 to 1.15, P for interaction <0.1). CONCLUSIONS: Serum AMH levels were not associated with fecundability in Chinese women of childbearing age. A suggestive association, however, was observed among women with cycle irregularity. Regular monitoring of AMH in fecundity prediction may be of limited value among healthy reproductive-aged Chinese women.