title: Sperm counts and sperm sex ratio in male infertility patients.
abstract: In recent years, investigators have noted a trend toward a declining proportion of male births in many industrialized nations. While men bear the sex-determining chromosome, the role of the female partner as it pertains to fertilization or miscarriage may also alter the gender ratio. We attempted to determine a man's secondary sex ratio (F1 generation) by directly examining the sex chromosomes of his sperm. We examined our male infertility clinic database for all men who had undergone a semen fluorescence in situ hybridization (FISH). Patient demographic and semen parameters were recorded. Chi-squared analysis was used to compare gender ratios (Y chromosomes/total chromosomes). Multivariable logistic regression was used to predict the odds of possessing a Y-bearing sperm after accounting for demographic and semen parameters. A total of 185 men underwent sperm FISH. For the entire cohort, the proportion of Y chromosome-bearing sperm was 51.5%. Men with less than five million motile sperm had a significantly lower proportion of Y chromosome-bearing sperm (50.8%) compared to men with higher sperm counts (51.6%; P=0.02). After multivariable adjustment, a higher sperm concentration, total motile sperm count and semen volume significantly increased the odds of having a Y chromosome-bearing sperm (P<0.01). As a man's sperm production declines, so does the proportion of Y chromosome-bearing sperm. Thus, a man's reproductive potential may predict his ability to sire male offspring.
authors: Department of Urology, Stanford University School of Medicine, Stanford, CA 94305, USA. berg@stanford.edu
authors: Michael L
authors: ML
authors: Eisenberg
authors: Lata
authors: L
authors: Murthy
authors: Kathleen
authors: K
authors: Hwang
authors: Dolores J
authors: DJ
authors: Lamb
authors: Larry I
authors: LI
authors: Lipshultz
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007248:Infertility, Male / Q000473:pathology*; D008297:Male; D012744:Sex Ratio; D013076:Sperm Count