title: Risks associated with subsequent pregnancy after one caesarean section: A prospective cohort study in a Nigerian obstetric population.
abstract: BACKGROUND
  Aversion for cesarean delivery is common in our practice and risks associated with caesarean section may contribute to this phenomenon.
  
  
  OBJECTIVE
  The objective of this study was to estimate the risks associated with subsequent pregnancies in women with one previous cesarean section in a low resource setting.
  
  
  METHODS
  A prospective cohort study carried out at two major tertiary maternity centers in Enugu.
  
  
  METHODS
  Maternal and perinatal outcomes were compared between women with one previous caesarean and women who had only previous vaginal deliveries.
  
  
  METHODS
  Analysis was performed with SPSS statistical software version 17.0 for windows (IBM Incorporated, Armonk, NY, USA) using descriptive and inferential statistics at 95% of the confidence level confidence.
  
  
  RESULTS
  A total of 870 women were studied. These were divided into 435 cases and 435 controls. The absolute risk of cesarean section in a subsequent pregnancy in women with one previous cesarean was 75.8% (95% confidence interval [CI]: 72.0, 80.0). Cesarean section was significantly commoner in women with one previous cesarean compared with those who had previous vaginal delivery (Relative risk [RR] =3.78; 95% CI: 1.8, 6.2). Placenta praevia (RR = 5.0; 95% CI: 2.6, 7.2.), labor dystocia (RR = 6.4, 95% CI: 3.2, 11.2) intrapartum hemorrhage (RR = 5.0, 95% CI: 2.1, 9.3) primary postpartum hemorrhage (RR = 5.0, 95% CI: 1.5, 4.3.), blood transfusion (RR = 6.0, 95% CI: 3.4, 10.6) and Newborn special care admission (RR = 2.5; 95% CI: 1.1, 4.9) were significantly more common in women with one previous cesarean compared with those with previous vaginal deliveries. The absolute risk of failed trial of vaginal birth after a cesarean was 45% (95% CI: 38.5, 51.5).
  
  
  CONCLUSIONS
  Women who have one previous C-section face a markedly increased risk of repeat caesarean sections and feto-maternal complications in subsequent pregnancies. There is a need for doctors in Nigeria to be mindful of these risks while offering primary cesarean section in this low resource setting.
authors.affiliation: Department of Obstetrics and Gynaecology, University of Nigeria Teaching Hospital, Ituku Ozalla, Nigeria.
authors.forename: C A
authors.initials: CA
authors.lastname: Iyoke
authors.forename: G O
authors.initials: GO
authors.lastname: Ugwu
authors.forename: F O
authors.initials: FO
authors.lastname: Ezugwu
authors.forename: O L
authors.initials: OL
authors.lastname: Lawani
authors.forename: H E
authors.initials: HE
authors.lastname: Onah
mesh_terms: D000328:Adult; D002585:Cesarean Section / Q000009:adverse effects* / Q000706:statistics & numerical data*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D009549:Nigeria / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology*; D011256:Pregnancy Outcome / Q000453:epidemiology*; D011446:Prospective Studies