A multicentre evaluation of the Elecsys anti-Müllerian hormone immunoassay for prediction of antral follicle count.

Research Question: What concentration of anti-Müllerian hormone (AMH) corresponds to an antral follicle count (AFC) >15 for determination of ovarian reserve?

Design: A prospective study conducted at 13 US fertility clinics in women aged 21-44 years who presented for AFC evaluation by transvaginal ultrasound. Serum samples were collected at the time of AFC evaluation (menstrual cycle day 2-4). AMH concentrations were measured by the Elecsys AMH immunoassay; oestradiol and follicle-stimulating hormone (FSH) concentrations were also measured. The serum AMH cut-off able to detect AFC >15 with high sensitivity was determined (derivation cohort). Clinical performance of the AMH assay at the derived cut-off was evaluated (validation cohort). Receiver operating characteristic (ROC) analyses were also performed.

Results: In the derivation cohort (n = 306), an optimal serum AMH cut-off value of 1.77 ng/ml was determined to correspond to AFC >15 with 89.63% sensitivity and 69.01% specificity, using the Elecsys AMH assay. In the validation cohort (n = 856), this 1.77 ng/ml cut-off could identify women with an AFC >15 with a sensitivity of 88.34% and a specificity of 68.29%; corresponding positive predictive and negative predictive values were 75.19% and 84.34%, respectively. ROC analyses demonstrated that AMH performed better than oestradiol or FSH in predicting AFC, with area under the curves of 85.7%, 57.1% and 69.7%, respectively, in the validation cohort.

Conclusion: The Elecsys AMH immunoassay provides a robust and fully automated method to measure serum AMH levels. Women with AMH values below the cut-off of 1.77 ng/ml are unlikely to have AFC >15.