Ovarian antral follicle subclasses and anti-Müllerian hormone during normal reproductive aging

Abstract

Context: The interindividual variation in the age-related decline of ovarian follicles is wide. Hence, it is important to identify reliable, sensitive, and specific markers to assess the ovarian reserve of the individual woman. Objective: The aim of this study was to characterize the relation between age and ovarian reserve parameters in a population of healthy women with regular menstrual cycle. Design and Setting: We conducted a prospective, population-based, cross-sectional study. Participants: A total of 366 health care workers aged 21-41 years employed at a University Hospital were included. Interventions: There were no interventions. Main Outcome Measures: Serum anti-Müllerian hormone (AMH) concentration, antral follicle count (AFC), antral follicle size categories (small: 2-4 mm; intermediate: 5-7 mm; and large: 8-10 mm), and ovarian volume were measured. Results: Serum AMH level declined by 5.6% peryear (95% confidence interval 3.7-7.4%, P < .001), AFC (2-10 mm) declined by 4.4% per year (3.2-5.7%, P < .001), and ovarian volume declined by 1.1% per year (0.2-2.0, P = .002), respectively. The mean proportion of small follicles decreased with age (P= .04), the proportion of intermediate follicles displayed no significant change with age (P = .58), and the mean proportion of large follicles increased with age (P < .001, area underthe curve 0.66], and with decreasing total AFC [odds ratio 1.04 per follicle (1.02-1.05), P < .001, area under the curve 0.62]. Conclusion: Chronological age was inversely related to serum AMH concentration, total AFC, and ovarian volume. Subclasses of AFC sized 2-4 and 5-7 mm decreased with increasing age, whereas AFC sized 8-10 mm increased with increasing age. Within AFC, a shift toward larger follicles with increasing age was observed. The occurrence of large follicles was more strongly related to biological age in terms of AMH and AFC than chronological age. Copyright © 2013 by The Endocrine Society.