Serum antimullerian hormone levels best reflect the reproductive decline with age in normal women with proven fertility: a longitudinal study.

Objective: The aim of this study was to assess which of the basal ovarian reserve markers provides the best reflection of the changes occurring in ovarian function over time (i.e., reproductive aging).
Design: Prospective longitudinal study.
Setting: Healthy volunteers in an academic research center.
Patient(s): Eighty-one women with normal reproductive performance during the course of their lives were longitudinally assessed. In this select group of women, becoming chronologically older was considered as a proxy variable for becoming older from a reproductive point of view.
Intervention(s): The women were assessed twice, with on average a 4-year interval (T(1) and T(2)). The number of antral follicles on ultrasound (AFC) and blood levels of antimullerian hormone (AMH), FSH, inhibin B, and E(2) were assessed.
Main Outcome Measure(s): Longitudinal changes of the markers mentioned and the consistency of these parameters over time.
Result(s): The mean ages at T(1) and T(2) were 39.6 and 43.6 years, respectively. Although AFC was strongly associated with age in a cross-sectional fashion, it did not change over time. The AMH, FSH, and inhibin B levels showed a significant change over time, in contrast to E(2) levels. The AMH and AFC were highly correlated with age both at T(1) and T(2), whereas FSH and inhibin B predominantly changed in women more than 40 years of age. To assess the consistency of these parameters over time, we investigated whether a woman's individual level above or below the mean of her age group at T(1) remained above or below the mean of her age group at T(2). Serum AMH concentrations showed the best consistency, with AFC as second best. The FSH and inhibin B showed only modest consistency, whereas E(2) showed no consistency at all.
Conclusion(s): These results indicate that serum AMH represents the best endocrine marker to assess the age-related decline of reproductive capacity.