Anogenital distance and variability in semen parameters.

The purpose of this study was to analyze whether the anogenital distance (AGD) was associated with variability in semen parameters. Semen parameters analyzed following the WHO guidelines and sperm DNA fragmentation were evaluated in 160 semen samples obtained over a period of a year from 16 healthy male volunteers. Two types of AGD measurements from the anus to the rear base of the scrotum (AGDAS) and to the cephalic insertion of the penis (AGDAP) were taken in each individual. The association between AGDs and semen parameters were studied using three statistical tools: a) general coefficient of variation (CV) and intra-individual coefficient of variation (CVi), b) general linear models for repeated measures, and c) mixed model fixed effects panel data. Men with shortened AGDAP have significantly greater intra-individual variability in sperm concentration, total sperm count, and normal sperm morphology. Conversely, greater total sperm motility was observed in men with long AGDAS. Shortened AGDAS was associated with less intra-individual variability of total sperm motility (progressive and non-progressive). AGD measurements were associated with the variability in semen parameters. AGD may be useful to determine intra-individual variability in semen parameters. ABBREVIATIONS: AGD: anogenital distance; AGDAP: anogenital distance from the anus to the cephalic insertion of the penis; AGDAS: anogenital distance from the anus to the rear base of the scrotum; AIC: Akaike information criteria; BMI: body mass index; CV: general coefficient of variation; CVi: intra-individual coefficient of variation; GLM: generalized linear model; PR+NP: total sperm motility.