title: Perinatal outcomes associated with maternal HIV infection: a systematic review and meta-analysis.
abstract: BACKGROUND
  The HIV pandemic affects 36·9 million people worldwide, of whom 1·5 million are pregnant women. 91% of HIV-positive pregnant women reside in sub-Saharan Africa, a region that also has very poor perinatal outcomes. We aimed to establish whether untreated maternal HIV infection is associated with specific perinatal outcomes.
  
  
  METHODS
  We did a systematic review and meta-analysis of the scientific literature by searching PubMed, CINAHL (Ebscohost), Global Health (Ovid), EMBASE (Ovid), and the Cochrane Central Register of Controlled Trials and four clinical trial databases (WHO International Clinical Trials Registry Platform, the Pan African Clinical Trials Registry, the ClinicalTrials.gov database, and the ISRCTN Registry) for studies published from Jan 1, 1980, to Dec 7, 2014. Two authors independently reviewed the studies retrieved by the scientific literature search, identified relevant studies, and extracted the data. We investigated the associations between maternal HIV infection in women naive to antiretroviral therapy and 11 perinatal outcomes: preterm birth, very preterm birth, low birthweight, very low birthweight, term low birthweight, preterm low birthweight, small for gestational age, very small for gestational age, miscarriage, stillbirth, and neonatal death. We included prospective and retrospective cohort studies and case-control studies reporting perinatal outcomes in HIV-positive women naive to antiretroviral therapy and HIV-negative controls. We used a random-effects model for the meta-analyses of specific perinatal outcomes. We did subgroup and sensitivity analyses and assessed the effect of adjustment for confounders. This systematic review and meta-analysis is registered with PROSPERO, number CRD42013005638.
  
  
  RESULTS
  Of 60,750 studies identified, we obtained data from 35 studies (20 prospective cohort studies, 12 retrospective cohort studies, and three case-control studies) including 53 623 women. Our meta-analyses of prospective cohort studies show that maternal HIV infection is associated with an increased risk of preterm birth (relative risk 1·50, 95% CI 1·24-1·82), low birthweight (1·62, 1·41-1·86), small for gestational age (1·31, 1·14-1·51), and stillbirth (1·67, 1·05-2·66). Retrospective cohort studies also suggest an increased risk of term low birthweight (2·62, 1·15-5·93) and preterm low birthweight (3·25, 2·12-4·99). The strongest and most consistent evidence for these associations is identified in sub-Saharan Africa. No association was identified between maternal HIV infection and very preterm birth, very small for gestational age, very low birthweight, miscarriage, or neonatal death, although few data were available for these outcomes. Correction for confounders did not affect the significance of these findings.
  
  
  CONCLUSIONS
  Maternal HIV infection in women who have not received antiretroviral therapy is associated with preterm birth, low birthweight, small for gestational age, and stillbirth, especially in sub-Saharan Africa. Research is needed to assess how antiretroviral therapy regimens affect these perinatal outcomes.
  
  
  BACKGROUND
  None.
authors.affiliation: Nuffield Department of Obstetrics and Gynaecology, The Women's Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK; Medical Research Council, Developmental Pathways for Health Research Unit, School of Medicine, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Chrystelle O O
authors.initials: CO
authors.lastname: Wedi
authors.affiliation: Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK.
authors.forename: Shona
authors.initials: S
authors.lastname: Kirtley
authors.affiliation: Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK.
authors.forename: Sally
authors.initials: S
authors.lastname: Hopewell
authors.affiliation: Nuffield Department of Obstetrics and Gynaecology, The Women's Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK.
authors.forename: Ruth
authors.initials: R
authors.lastname: Corrigan
authors.affiliation: Nuffield Department of Obstetrics and Gynaecology, The Women's Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK.
authors.forename: Stephen H
authors.initials: SH
authors.lastname: Kennedy
authors.affiliation: Nuffield Department of Obstetrics and Gynaecology, The Women's Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK; Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK; Medical Research Council, Developmental Pathways for Health Research Unit, School of Medicine, University of the Witwatersrand, Johannesburg, South Africa. Electronic address: joris.hemelaar@obs-gyn.ox.ac.uk.
authors.forename: Joris
authors.initials: J
authors.lastname: Hemelaar
mesh_terms: D005260:Female; D015658:HIV Infections / Q000503:physiopathology / Q000635:transmission* / Q000821:virology; D015497:HIV-1 / Q000502:physiology; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D008297:Male; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000503:physiopathology* / Q000821:virology; D011256:Pregnancy Outcome