title: The relationship between obesity and fecundity.
abstract: OBJECTIVE
  Obesity is an important factor that might reduce fecundity. In order to determine the underlying physiological mechanisms and risk factors, the obesity-fecundity association is investigated in relation to parity, menstrual cycle regularity, smoking habits, and age.
  
  
  METHODS
  This was a retrospective cohort study of 22,840 women who gave birth between January 2006 and January 2007 in the Dr Zekai Tahir Burak Women's Health Research and Education Hospital. Age, parity, prepregnancy body mass index (BMI) values, time to pregnancy data related to smoking, and reproductive, medical, and gynecological history were obtained from the medical records.
  
  
  RESULTS
  Fecundity was reduced for overweight and obese women compared with optimal weight women, and this reduction was more evident for obese primiparous women. Fecundity remained reduced for overweight and obese women with normal menstrual cycles. Obese and overweight women were found to smoke significantly more than the optimal weight group.
  
  
  CONCLUSIONS
  Obesity was found to be associated with reduced fecundity for all weight-adjusted groups of women and persisted for women with regular cycles. Weight loss should be encouraged initially during the treatment of infertile overweight and obese women.
authors.affiliation: Department of Perinatology, Dr Zekai Tahir Burak Women's Health Research and Education Hospital, Ankara, Turkey.
authors.forename: Nafiye
authors.initials: N
authors.lastname: Yilmaz
authors.forename: Sevtap
authors.initials: S
authors.lastname: Kilic
authors.forename: Mine
authors.initials: M
authors.lastname: Kanat-Pektas
authors.forename: Cavidan
authors.initials: C
authors.lastname: Gulerman
authors.forename: Leyla
authors.initials: L
authors.lastname: Mollamahmutoglu
mesh_terms: D000328:Adult; D015992:Body Mass Index; D015897:Comorbidity; D005260:Female; D005298:Fertility; D006801:Humans; D007247:Infertility, Female / Q000453:epidemiology*; D009765:Obesity / Q000453:epidemiology*; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D014421:Turkey / Q000453:epidemiology; D016387:Women's Health; D055815:Young Adult