title: Chlamydia and gonorrhoea infections and the risk of adverse obstetric outcomes: a retrospective cohort study.
abstract: OBJECTIVE
  To examine the association between prior chlamydia and gonorrhoea infections and adverse obstetric outcomes.
  
  
  METHODS
  Records of women resident in New South Wales, Australia with a singleton first birth during 1999-2008 were linked to chlamydia and gonorrhoea notifications using probabilistic linkage. Obstetric outcomes and potential confounders were ascertained from the birth record. Logistic regression, adjusted for potential confounders was used to estimate the association between a disease notification prior to the birth and adverse birth outcomes: spontaneous preterm birth (SPTB), small for gestational age (SGA) and stillbirth.
  
  
  RESULTS
  Among 354 217 women, 1.0% (n=3658) had a prior chlamydia notification; 0.06% (n=196) had a prior gonorrhoea notification. The majority of notifications (>80%) occurred before the estimated conception date. 4.1% of women had a SPTB, 12.1% had a SGA baby and 0.6% of women had a stillbirth. Among women with a prior chlamydia notification, the risk of SPTB and stillbirth was increased, aOR 1.17 (95% CI 1.01 to 1.37) and aOR 1.40 (95% CI 1.00 to 1.96) respectively but there was no association with SGA, aOR 0.99 (95% CI 0.89 to 1.09). For women with gonorrhoea the risks for SPTB, stillbirth and SGA were respectively aOR 2.50 (95%CI 1.39 to 4.50), 2.35 (95% CI 0.58 to 9.56) and 0.98 (95% CI 0.58 to 1.68). Among women with a prior chlamydia diagnosis, the risk of SPTB did not differ between women diagnosed >1 year prior to conception, within the year prior to conception or during the pregnancy, (p=0.9).
  
  
  CONCLUSIONS
  Sexually transmissible infections in pregnancy and the preconception period may be important in predicting pregnancy outcomes.
authors.affiliation: University of New South Wales, , Sydney, New South Wales, Australia.
authors.forename: Bette
authors.initials: B
authors.lastname: Liu
authors.forename: Christine L
authors.initials: CL
authors.lastname: Roberts
authors.forename: Marilyn
authors.initials: M
authors.lastname: Clarke
authors.forename: Louisa
authors.initials: L
authors.lastname: Jorm
authors.forename: Jennifer
authors.initials: J
authors.lastname: Hunt
authors.forename: James
authors.initials: J
authors.lastname: Ward
mesh_terms: D001315:Australia / Q000453:epidemiology; D002690:Chlamydia Infections / Q000150:complications* / Q000453:epidemiology; D018563:Disease Notification / Q000706:statistics & numerical data*; D005260:Female; D006069:Gonorrhea / Q000150:complications* / Q000453:epidemiology; D006801:Humans; D007231:Infant, Newborn; D009517:New South Wales / Q000453:epidemiology; D016742:Preconception Care; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000382:microbiology*; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D018570:Risk Assessment
keywords: Chlamydia Infection; Epidemiology (General); Public Health; Reproductive Health