Anti-mullerian hormone (AMH) values can be measured with a simple blood test. In females, AMH expression has been observed in granulosa cells of preantral ovarian follicles and is produced by these cells until menopause. The Beckman Coulter Access AMH assay can be used to aid in the assessment of ovarian reserve in women presenting to fertility clinics. Although AMH concentrations decrease with age, studies have shown that the day-to-day variability of AMH concentrations in menstruating women is low.