The relationship between anogenital distance and azoospermia in adult men

Anogenital distance (AGD) is a marker for endocrine disruption in animal studies in which decreased male AGD has been associated with testicular dysfunction. The objective of the study was to investigate whether anogenital distance could distinguish men with obstructive azoospermia (OA) from those with nonobstructive azoospermia (NOA). To accomplish this, azoospermic men were recruited and evaluated at a men's reproductive health clinic in Houston, TX. Anogenital distance (the distance from the posterior aspect of the scrotum to the anal verge) and penile length (PL) were measured using digital calipers. Testis size was estimated by physical examination. Logistic regression was used to compare AGD lengths in men with OA and men with NOA. A total of 69 OA men (mean age: 44.2 ± 9.2) and 29 NOA men (mean age: 32.8 ± 4.8) were recruited. The NOA men possessed significantly shorter mean AGD than the men with OA (AGD: 36.3 vs. 41.9 mm, p = 0.01). An AGD of less than 30 mm, had a 91% specificity in accurately classifying NOA. Moreover, after adjustment for age, race, and BMI, an AGD of less than 30 mm yielded a significantly increased odds of NOA compared to OA (OR 5.6, 95% CI 1.0, 30.7). In summary, AGD may provide a novel metric for assessing testicular function in men and in distinguishing OA from NOA.