Efficacy of predictive models for polycystic ovary syndrome using serum levels of two antimüllerian hormone isoforms (proAMH and AMH).

OBJECTIVE

To compare total antimüllerian hormone (AMH), proAMH, AMH, and the ratio of the two forms in predictive models for polycystic ovary syndrome (PCOS) diagnosis. Total AMH consists of proAMH (inactive precursor) and AMH (receptor-competent), but neither isoform has been tested individually for their ability to predict PCOS diagnosis.

DESIGN

Cross-sectional study using biobanked samples collected between July 2008 and January 2010.

SETTING

Not applicable.

PATIENT(S): Overweight, premenopausal women aged 18-45 years with PCOS (n = 45, with 21 fulfilling National Institutes of Health diagnostic criteria and 24 fulfilling European Society for Human Reproduction and Embryology/American Society for Reproductive Medicine (ESHRE) criteria, but not National Institutes of Health criteria) and without PCOS (n = 23 controls).

INTERVENTION(S): None.

MAIN OUTCOME MEASURE(S): Serum concentrations of proAMH and total AMH (proAMH and AMH combined) were determined by immunoassay. The AMH concentrations were calculated by subtraction ([AMH] = [total AMH] - [proAMH]). Relative levels of proAMH were expressed as the AMH prohormone index (API = [ProAMH]/[Total AMH] × 100).

RESULT(S): In women with PCOS, total AMH, proAMH, and AMH levels were higher, and the API was lower (P=.010), than in controls indicating increased conversion of proAMH to AMH. Receiver-operating characteristic analysis for proAMH (area under the curve [AUC] = 0.82), AMH (AUC = 0.86), and API (AUC = 0.70) did not improve the prediction for PCOS when compared with total AMH (AUC = 0.86).

CONCLUSION(S): The proAMH and AMH do not appear to improve the ability to predict a diagnosis of PCOS beyond total AMH assays. However, the ratio of inactive proAMH precursor to receptor-competent AMH (API) differs in women with PCOS relative to unaffected controls indicating that AMH signaling mechanisms may be altered in women with PCOS.