title: The association between timing of initiation of antenatal care and stillbirths: a retrospective cohort study of pregnant women in Cape Town, South Africa.
abstract: BACKGROUND
  There is renewed interest in stillbirth prevention for lower-middle income countries. Early initiation of and properly timed antenatal care (ANC) is thought to reduce the risk of many adverse birth outcomes. To this end we examined if timing of the first ANC visit influences the risk of stillbirth.
  
  
  METHODS
  We conducted an analysis of a retrospective cohort of women (n = 34,671) with singleton births in a public perinatal service in Cape Town, South Africa. The main exposure was the gestational age at the first ANC visit. Bivariable analyses examining maternal characteristics by stillbirth status and gestational age at the first ANC visit, were conducted. Logistic regression, adjusting for maternal characteristics, was conducted to determine the risk of stillbirth.
  
  
  RESULTS
  Of the 34,671 women who initiated ANC, 27,713 women (80%) were retained until delivery. The population stillbirth rate was 4.3 per 1000 births. The adjusted models indicated there was no effect of gestational age at first ANC visit on stillbirth outcomes when analyzed as a continuous variable (aOR 1.01; 95% CI: 0.99-1.04) or in trimesters (2nd Trimester aOR 0.78, 95% CI: 0.39-1.59; 3rd Trimester OR 1.03, 95% CI: 0.50-2.13, both with 1st Trimester as reference category). The findings were unchanged in sensitivity analyses of unobserved outcomes in non-retained women.
  
  
  CONCLUSIONS
  The timing of a woman's first ANC visit may not be an important determinant of stillbirths in isolation. Further research is required to examine how quality of care, incorporating established, effective biomedical interventions, influences outcomes in this setting.
authors.affiliation: The South African Department of Science and Technology/National Research Foundation (DST/NRF) Centre of Excellence in Epidemiological Modeling and Analysis (SACEMA), Stellenbosch University, c/o StIAS, Private Bag X1, Matieland, Stellenbosch 7602, South Africa. roxanne.beauclair@gmail.com.
authors.forename: Roxanne
authors.initials: R
authors.lastname: Beauclair
authors.forename: Greg
authors.initials: G
authors.lastname: Petro
authors.forename: Landon
authors.initials: L
authors.lastname: Myer
mesh_terms: D000328:Adult; D044383:Black People / Q000706:statistics & numerical data; D005260:Female; D005865:Gestational Age; D006801:Humans; D008423:Maternal Age; D011247:Pregnancy; D011264:Pregnancy Trimesters; D011295:Prenatal Care / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D013019:South Africa / Q000453:epidemiology; D050497:Stillbirth / Q000453:epidemiology* / Q000208:ethnology; D013997:Time Factors; D055815:Young Adult