title: Mode of delivery and the probability of subsequent childbearing: a population-based register study.
abstract: OBJECTIVE
  To investigate the relationship between mode of first delivery and probability of subsequent childbearing.
  
  
  METHODS
  Population-based study.
  
  
  METHODS
  Nationwide study in Sweden.
  
  
  METHODS
  A cohort of 771 690 women who delivered their first singleton infant in Sweden between 1992 and 2010.
  
  
  METHODS
  Using Cox's proportional-hazards regression models, risks of subsequent childbearing were compared across four modes of delivery. Hazard ratios (HRs) were calculated, using 95% confidence intervals (95% CIs).
  
  
  METHODS
  Probability of having a second and third child; interpregnancy interval.
  
  
  RESULTS
  Compared with women who had a spontaneous vaginal first delivery, women who delivered by vacuum extraction were less likely to have a second pregnancy (HR 0.96, 95% CI 0.95-0.97), and the probabilities of a second childbirth were substantially lower among women with a previous emergency caesarean section (HR 0.85, 95% CI 0.84-0.86) or an elective caesarean section (HR 0.82, 95% CI 0.80-0.83). There were no clinically important differences in the median time between first and second pregnancy by mode of first delivery. Compared with women younger than 30 years of age, older women were more negatively affected by a vacuum extraction with respect to the probability of having a second child. A primary vacuum extraction decreased the probability of having a third child by 4%, but having two consecutive vacuum extraction deliveries did not further alter the probability.
  
  
  CONCLUSIONS
  A first delivery by vacuum extraction does not reduce the probability of subsequent childbearing to the same extent as a first delivery by emergency or elective caesarean section.
authors.affiliation: Division of Clinical Epidemiology, Department of Medicine, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Elvander
authors.affiliation: Department of Sociology, Stockholm University Demography Unit, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Dahlberg
authors.affiliation: Department of Sociology, Stockholm University Demography Unit, Stockholm, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Andersson
authors.affiliation: Division of Clinical Epidemiology, Department of Medicine, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Cnattingius
mesh_terms: D000328:Adult; D001723:Birth Rate; D002585:Cesarean Section / Q000523:psychology / Q000706:statistics & numerical data*; D036861:Delivery, Obstetric / Q000523:psychology / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011336:Probability; D016016:Proportional Hazards Models; D012042:Registries / Q000706:statistics & numerical data*; D043762:Reproductive Behavior / Q000523:psychology / Q000706:statistics & numerical data*; D013548:Sweden / Q000453:epidemiology; D014620:Vacuum Extraction, Obstetrical / Q000523:psychology / Q000706:statistics & numerical data*
keywords: Elective caesarean section; emergency caesarean section; mode of delivery; subsequent childbearing; vacuum extraction