title: Recurrence of preterm birth and perinatal mortality in northern Tanzania: registry-based cohort study.
abstract: OBJECTIVE
  To estimate the recurrence risk of preterm delivery and estimate the perinatal mortality in repeated preterm deliveries.
  
  
  METHODS
  Prospective study in Tanzania of 18 176 women who delivered a singleton between 2000 and 2008 at KCMC hospital. The women were followed up to 2010 for consecutive births. A total of 3359 women were identified with a total of 3867 subsequent deliveries in the follow-up period. Recurrence risk of preterm birth and perinatal mortality was estimated using log-binomial regression and adjusted for potential confounders.
  
  
  RESULTS
  For women with a previous preterm birth, the risk of preterm birth in a subsequent pregnancy was 17%. This recurrence risk was estimated to be 2.7-fold (95% CI: 2.1-3.4) of the risk of women with a previous term birth. The perinatal mortality of babies in a second preterm birth of the same woman was 15%. Babies born at term who had an older sibling that was born preterm had a perinatal mortality of 10%. Babies born at term who had an older sibling who was also born at term had a perinatal mortality of 1.7%.
  
  
  CONCLUSIONS
  Previous delivery of a preterm infant is a strong predictor of future preterm births in Tanzania. Previous or repeated preterm births increase the risk of perinatal death substantially in the subsequent pregnancy.
authors.affiliation: Kilimanjaro Christian Medical University College, Moshi, Tanzania. jmmahande@yahoo.com
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mahande
authors.forename: Anne K
authors.initials: AK
authors.lastname: Daltveit
authors.forename: Joseph
authors.initials: J
authors.lastname: Obure
authors.forename: Blandina T
authors.initials: BT
authors.lastname: Mmbaga
authors.forename: Gileard
authors.initials: G
authors.lastname: Masenga
authors.forename: Rachel
authors.initials: R
authors.lastname: Manongi
authors.forename: Rolv T
authors.initials: RT
authors.lastname: Lie
mesh_terms: D000328:Adult; D036861:Delivery, Obstetric / Q000706:statistics & numerical data; D003906:Developing Countries; D004812:Epidemiologic Methods; D005260:Female; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D010298:Parity; D054238:Perinatal Mortality; D011225:Pre-Eclampsia / Q000453:epidemiology; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology*; D012008:Recurrence; D012042:Registries; D013636:Tanzania / Q000453:epidemiology; D047929:Term Birth
keywords: perinatal death; preterm birth; recurrence risk; risk factors