Is antral follicle count (AFC) more than a marker of oocyte number? Women with infertility have lower AFC than normal women

Abstract

OBJECTIVE: AFC has been used as a marker of ovarian aging, and may be associated with decreased odds of pregnancy in women undergoing ART. We sought to determine whether ovulatory infertile women have different AFC than a population-based cohort of ovulatory controls. DESIGN: Cross-sectional. MATERIALS AND METHODS: Subjects included women aged 25-45. The infertile group included women undergoing their first IVF cycle in our clinic. The control group was comprised of normal, ovulatory women aged 25-45 enrolled in the OVA (Ovarian Aging) study. Antral follicle count was performed by transvaginal ultrasound in a cycle prior to IVF in infertile women, and between day 2 and 5 of the menstrual cycle for controls. Women with oligo- or anovulation, surgically diagnosed endometriosis, ovarian failure, use of an oocyte donor or gestational surrogate, or ovarian surgery were excluded. Age was stratified into 5-year intervals. Median AFCs were compared between the 2 groups by age stratum using the median test. RESULTS: 1491 infertile women and 423 controls were included. Median AFCs were lower in infertile women than in controls across ages 25-40. AFCs did not differ significantly between infertile and control women aged 41-45.Tabled 1AFCs among infertile and control women, by age groupInfertile (AFC)Control (AFC)AgeNMedianRangeNMedianRangeP-value25-30941610-5371214-400.000231-35469115-48131151-35<0.000136-4064291-52130131-63<0.000141-4528681-339171-460.74 Open table in a new tab CONCLUSIONS: AFC has been shown to correlate with markers of ovarian aging including FSH, AMH and number of oocytes collected following stimulation. This is the first study to compare AFC in an infertile population to that seen in the general population. The lowered AFC in the infertile group suggests factors affecting the size of the remaining follicle pool may also affect oocyte quality and likelihood of conception.