title: [Paternal age and fertility].
abstract: Variations of the male partner fertility according to his age are difficult to study, because of bias represented by some decrease of both sexual activity and fecundity of the female partner beyond 35 years old. The few studies which are available show that sperm concentration as percentage of normal forms, are stable with age. The percentage of motility is the only parameter which decreases systematically with age according to all studies. Nevertheless, sperm fertilizing capacity does not seem to be decreased. FIVNAT data allow to analyse almost 30,000 IVF cycles for tubal sterility; they confirm the absence of an important alteration of semen characteristics with age. Despite a significant decrease--even moderate--of the mean fertilization rates, the pregnancy rates remain roughly constant for a given range of maternal age.
authors.affiliation: Faculté de médecine, Laboratoire d'Histologie, Embryologie, Biologie de la Reproduction, Lyon.
authors.forename: J F
authors.initials: JF
authors.lastname: Guérin
authors.forename: J
authors.initials: J
authors.lastname: de Mouzon
mesh_terms: D000328:Adult; D015982:Bias; D005260:Female; D005307:Fertilization in Vitro / Q000706:statistics & numerical data*; D005602:France; D006801:Humans; D007246:Infertility / Q000209:etiology* / Q000628:therapy*; D008297:Male; D008423:Maternal Age; D008875:Middle Aged; D010331:Paternal Age; D011247:Pregnancy; D011256:Pregnancy Outcome; D012042:Registries; D013081:Sperm Motility