New automated antimüllerian hormone assays are more reliable than the manual assay in patients with reduced antral follicle count.

Objective: To compare the strength of the relationship between antral follicle count (AFC) and serum antimüllerian hormone (AMH) concentrations obtained with two automated and one manual AMH assays in three different AFC populations.

Design: Prospective cohort study.

Setting: University-affiliated IVF-ET center.

Patient(s): Frozen-thawed serum samples of 211 assisted conception candidates, aged 24-43 years.

Intervention(s): Serum AMH was measured using one manual (AMH Gen II) and two fully automated (Access AMH and Elecsys AMH) assays. Antral follicle count was performed under strictly standardized conditions and sorted into three groups according to tercile values: low AFC (3-12 follicles; n = 73), intermediate AFC (13-20 follicles; n = 65), and high AFC (21-84 follicles; n = 73).

Main Outcome Measure(s): Strength of correlation between AMH levels and AFC.

Result(s): Overall, AMH levels were lower with Access AMH (-16%) and Elecsys AMH (-20%) than with AMH Gen II. Remarkably, the strength of correlations between AFC and circulating AMH levels was the same with the three assays (r = 0.83). Yet in the low AFC group, serum AMH levels obtained by Access AMH and Elecsys AMH showed a stronger correlation with AFC (r = 0.63 and r = 0.65, respectively) than the AMH Gen II (r = 0.52), a phenomenon that was not observed in the remaining AFC groups.

Conclusion(s): As compared with conventional AMH Gen II assay results, [1] serum AMH concentrations were -16% and -20% lower with Access AMH and Elecsys AMH, respectively; and [2] automated assays were more strongly correlated to AFC in the subset of patients with reduced follicle count.