Anti Mullerian Hormone and Inhibin B: Discriminatory Markers of Azoospermia?

Abstract

Anti mullerian hormone (AMH) and inhibin B are synthesised and secreted by the male gonads. The objective of this ongoing study is to investigate if circulating concentrations of AMH and/or inhibin B could be useful in discriminating obstructive and non-obstructive azoospermia in men. In a prospective study, blood samples were taken from men with non-obstructive azoospermia (n=10), obstructive azoospermia (n=8) and fertile controls (n=19). Blood samples were collected in plain tubes and serum was separated and frozen until assays were carried out. AMH and inhibin B were measured using commercial assays. AMH concentrations in the non-obstructive azoospermia males were ∼50% lower (mean ±stdev; 4±2.4ng/ml, P=0.003) than the controls (9.3±5.2ng/ml). Levels of AMH in the obstructive azoospermia group were not significantly altered (6.4±4.6ng/ml) from the control or the non-obstructive azoospermia males. Inhibin B levels were undetectable in 7 patients (<10pg/ml) and 25pg/ml in one patient in the non-obstructive azoospermia group. The levels of inhibin B in the obstructive azoospermia males (175±107pg/ml) were significantly higher (∼17 fold, P<0.001) than the non-obstructive azoospermia males. Serum inhibin B in the control group was 181±58.5pg/ml similar to the obstructive azoospermia males. Serum AMH and inhibin B are significantly decreased in non-obstructive azoospermia compared to the controls. However, this pilot study shows that inhibin B is better than AMH in discriminating between obstructive and non-obstructive azoospermia.