title: Estimation of the frequency of involuntary infertility on a nation-wide basis.
abstract: BACKGROUND
  Assessing couple fecundity on a nation-wide basis without excluding couples who eventually remain infertile is challenging. Our aim was to describe couple fecundity (in terms of frequency of involuntary infertility) among the general population living in France.
  
  
  METHODS
  We used a current-duration design. A random sample of 64 262 households was selected in 2007-2008, allowing us to identify 15 810 women aged 18-44 years. Eligible women (n= 1089) were those having regular sexual intercourse with a male partner, not using any method of contraception and not having delivered in the previous 3 months. These women reported information on the current duration of unprotected intercourse (CDUI, the time elapsed between the start of the period of unprotected intercourse and the time of inclusion in the study). The CDUI distribution was used to estimate the frequency of involuntary infertility, using a newly developed statistical technique that does not require couples to be followed up until the end of the period of unprotected intercourse.
  
  
  RESULTS
  CDUI was defined for 867 women. An estimated 46% of couples had no detected pregnancy conceived during the first 6 months of unprotected intercourse [95% confidence interval (CI), 36-56%]. The proportions of couples with no detected pregnancy within 12 and 24 months were 24% (19-30%) and 11% (8-14%), respectively.
  
  
  CONCLUSIONS
  These results constitute one of the few descriptions of the fecundity of a nation-wide representative sample of couples from the general population, not limited to couples who eventually conceived or to those resorting to medical help.
authors.affiliation: Inserm, Institut Albert Bonniot (U823), Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, F-38042 Grenoble, France. remy.slama@ujf-grenoble.fr
authors.forename: R
authors.initials: R
authors.lastname: Slama
authors.forename: O K H
authors.initials: OK
authors.lastname: Hansen
authors.forename: B
authors.initials: B
authors.lastname: Ducot
authors.forename: A
authors.initials: A
authors.lastname: Bohet
authors.forename: D
authors.initials: D
authors.lastname: Sorensen
authors.forename: L
authors.initials: L
authors.lastname: Giorgis Allemand
authors.forename: M J C
authors.initials: MJ
authors.lastname: Eijkemans
authors.forename: L
authors.initials: L
authors.lastname: Rosetta
authors.forename: J C
authors.initials: JC
authors.lastname: Thalabard
authors.forename: N
authors.initials: N
authors.lastname: Keiding
authors.forename: J
authors.initials: J
authors.lastname: Bouyer
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D007247:Infertility, Female / Q000453:epidemiology*; D043762:Reproductive Behavior; D013997:Time Factors