title: Fetal or infant death in twin pregnancy: neurodevelopmental consequence for the survivor.
abstract: OBJECTIVE
  To determine the neurodevelopmental morbidity in the surviving twin after fetal or infant death of the co-twin.
  
  
  METHODS
  Twin pregnancies with an antepartum or infant death delivered between 1981 and 1992 were identified from the Northern Perinatal Mortality Survey. Information on the neurodevelopmental morbidity of infant survivors of a deceased co-twin was obtained by a questionnaire sent to the community paediatrician or general practitioner.
  
  
  RESULTS
  A total of 111 children who survived infancy after the fetal death of the co-twin (group 1) and 142 from liveborn twin pairs in which one twin died in infancy (group 2) were traced. Responses were received from 97 (87%) and 130 (92%) respectively. In group 1, the cerebral palsy prevalence was 93 (95% confidence interval (CI) 43 to 169) per 1000 infant survivors; it was more common in like-sex pairs (8/70) with a prevalence of 114 (95% CI 51 to 213) compared with 45 (95% CI 1 to 228) per 1000 infant survivors in unlike-sex pairs (1/22). The overall prevalence of neurodevelopmental morbidity (including developmental delay) was 175 (95% CI 106 to 266) per 1000. In group 2, the cerebral palsy prevalence was 154 (95% CI 84 to 223) per 1000 infant survivors in like-sex (16/104) and 77 (95% CI 9 to 251) in unlike-sex (2/26) survivors; the overall prevalence of neurodevelopmental morbidity was 246 (95% CI 172 to 320) per 1000.
  
  
  CONCLUSIONS
  The risk of cerebral palsy is increased in the surviving twin after a fetal or infant co-twin death compared with the general twin population. Like-sex twins are at greater risk than unlike-sex. The probable cause, in addition to the consequences of prematurity, is twin-twin transfusion problems associated with monochorionicity.
authors.affiliation: Department of Epidemiology and Public Health, School of Public Health, University of Newcastle, Newcastle upon Tyne NE2 4HH, UK. svetlana.glinianaia@ncl.ac.uk
authors.forename: S V
authors.initials: SV
authors.lastname: Glinianaia
authors.forename: P O D
authors.initials: PO
authors.lastname: Pharoah
authors.forename: C
authors.initials: C
authors.lastname: Wright
authors.forename: J M
authors.initials: JM
authors.lastname: Rankin
mesh_terms: D001927:Brain Diseases / Q000196:embryology / Q000453:epidemiology / Q000209:etiology*; D002423:Cause of Death; D002547:Cerebral Palsy / Q000196:embryology / Q000453:epidemiology / Q000209:etiology; D004200:Diseases in Twins / Q000196:embryology / Q000453:epidemiology / Q000209:etiology*; D004739:England / Q000453:epidemiology; D005260:Female; D005313:Fetal Death; D005330:Fetofetal Transfusion / Q000150:complications; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D015995:Prevalence; D012307:Risk Factors; D012737:Sex Factors