title: Human live birth and sperm-sex ratios compared.
abstract: The human secondary sex ratio is compared with the percentage of Y-chromosome bearing spermatozoa in human semen. Live birth sex ratio is about 51.3%, whereas the overall percentage of Y-chromosome bearing spermatozoa in our study samples was 50.3%, i.e. 1% closer to the proportion expected by Mendelian segregation. The observed difference between live birth and sperm-sex ratios was significant (P < 0.0001). A possible effect of male age on the percentage Y-bearing spermatozoa was found to be non-significant.
authors.affiliation: University Pompeu Fabra, Department of Economics, Barcelona, Spain and Genetics & IVF Institute, 3020 Javier Road, Fairfax, VA 22031, USA.
authors.forename: J
authors.initials: J
authors.lastname: Graffelman
authors.forename: E F
authors.initials: EF
authors.lastname: Fugger
authors.forename: K
authors.initials: K
authors.lastname: Keyvanfar
authors.forename: J D
authors.initials: JD
authors.lastname: Schulman
mesh_terms: D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D011247:Pregnancy; D012044:Regression Analysis; D012744:Sex Ratio; D013094:Spermatozoa / Q000648:ultrastructure*; D014998:Y Chromosome