Age-Specific Nomograms for Antral Follicle Count in Fertile and Infertile Indian Women: A Comparative Study.

 The aim of this study was to develop age-specific nomograms for antral follicle count (AFC) in fertile and infertile Indian women and (2) to compare the influence of age on AFC in both groups.  It is a prospective cross-sectional study in a tertiary-care hospital in north-central India.  One-thousand four-hundred seventy-eight fertile and 1,447 infertile women (primary infertility) of reproductive age (18-49 years) were recruited. One-thousand one-hundred eighty-one fertile and 1,083 infertile women fulfilled the selection criteria for the study. Transvaginal ultrasonography was done on the second or third day of the menstrual cycle.  Age-specific nomograms for AFC were built for the 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles in both groups. Correlation and regression analysis was done to estimate the relationship between the study variables. Statistical analysis was done by using IBM SPSS Statistics for Windows, version 20.  At every age, each percentile value of AFC was lower in infertile than in fertile women. The decline of AFC with increasing age was linear in both fertile (  = - 0.431,  < 0.001) and infertile (  = - 0.520,  < 0.001) women; however, the rate was higher in the latter (0.50 follicle/year) than in former (0.44 follicle/year) group. The variation in AFC explained by age was 16.3% in fertile and 22.7% in infertile women.  AFC decreased linearly with advancing age in both fertile and infertile women, but more rapidly in the latter. The age only modestly explained the decline of AFC. The age-specific percentile thresholds for AFC should be used instead of age-independent constant thresholds in infertility counselling.