title: Live births, cesarean sections and the development of menstrual abnormalities.
abstract: OBJECTIVE
  To examine the relationship between number of livebirths and cesarean sections on the development of menstrual abnormalities.
  
  
  METHODS
  The effect of number of livebirths and cesarean sections on menstrual abnormalities in the late reproductive period was evaluated using data from the Harvard Study of Moods and Cycles.
  
  
  RESULTS
  There were 298 women with no livebirths and 606 women with livebirths of which 184 had a history of cesarean section. Among all women, increasing number of livebirths was associated with an increasing trend in reported heavy menses, prolonged flow >6 days, and a decreasing trend in reported dysmenorrhea. This effect was amplified among women with a history of cesarean section.
  
  
  CONCLUSIONS
  Increasing number of livebirths is associated with heavy and prolonged menstrual flow during the late reproductive period. This association is particularly stronger in women with a history of cesarean section.
authors.affiliation: School of Public Health, Harvard University, Boston, MA, USA.
authors.forename: H A
authors.initials: HA
authors.lastname: Abenhaim
authors.forename: B L
authors.initials: BL
authors.lastname: Harlow
mesh_terms: D000328:Adult; D002585:Cesarean Section / Q000706:statistics & numerical data*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004412:Dysmenorrhea / Q000453:epidemiology / Q000209:etiology; D005260:Female; D006801:Humans; D050498:Live Birth; D008404:Massachusetts / Q000453:epidemiology; D008599:Menstruation Disturbances / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D011795:Surveys and Questionnaires