title: Prospective risk of stillbirth: monochorionic diamniotic twins vs. dichorionic twins.
abstract: OBJECTIVE
  To determine reliably the risk of stillbirth among twin pregnancies.
  
  
  METHODS
  A data analysis of 3241 and 6581 women with monochorionic diamniotic (MD) and dichorionic (DD) twins, respectively, who gave birth at ≥22 weeks of gestation.
  
  
  RESULTS
  The prospective risk (per 1000 women) of stillbirth, 25.3 and 11.5 at gestational week 22, decreased to <10.0 at gestational weeks 31 and 28 among the MD and DD twins, respectively. After single intrauterine fetal death, the co-twin died in utero or within 7 days of life more frequently among MD twins than among DD twins [42.7% (35/82) vs. 2.6% (2/76); relative risk, 16.2; 95% confidence interval, 4.0-65.1].
  
  
  CONCLUSIONS
  Women with MD twins were 2.2-fold more likely to experience stillbirth than women with DD twins. The prospective risks of stillbirth were <1.0% for both groups of women at ≥32 weeks of gestation.
authors.affiliation: Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Sapporo, Japan. mmamoru@med.hokudai.ac.jp
authors.forename: Mamoru
authors.initials: M
authors.lastname: Morikawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamada
authors.forename: Takahiro
authors.initials: T
authors.lastname: Yamada
authors.forename: Shoji
authors.initials: S
authors.lastname: Sato
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Cho
authors.forename: Hisanori
authors.initials: H
authors.lastname: Minakami
mesh_terms: D000650:Amnion / Q000033:anatomy & histology; D002823:Chorion / Q000033:anatomy & histology; D004200:Diseases in Twins / Q000401:mortality; D005260:Female; D005313:Fetal Death / Q000453:epidemiology; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007564:Japan / Q000453:epidemiology; D008297:Male; D054238:Perinatal Mortality; D011247:Pregnancy; D059285:Pregnancy, Twin; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors; D050497:Stillbirth / Q000453:epidemiology*; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic