title: Risk for gastroschisis in primigravidity, length of sexual cohabitation, and change in paternity.
abstract: BACKGROUND
  Maternal epidemiologic similarities between gastroschisis and preeclampsia have led to the objective of evaluating the risk for gastroschisis related to primigravidity, change in paternity, and length of cohabitation, considered as risk factors for preeclampsia.
  
  
  METHODS
  The subjects were 288 newborns with isolated gastroschisis and 576 normal controls, matched by maternal age. They were ascertained in the Estudio Colaborativo Latino Americano de Malformaciones Congenitas hospital network of 10 South American countries between 1982 and 2005. Epidemiologic variables were compared among controls, between primigravidas and multigravidas, between multigravidas who had and had not changed partners, and between mothers with short and long cohabitation times with their partners. Risks associated with primigravidity, short cohabitation time, and changing paternity, as well as their combinations, were calculated. An eventual interaction between maternal age and the three risk factors was assessed.
  
  
  RESULTS
  Only a short cohabitation time showed a significant OR for gastroschisis (OR = 2.36, 95% CI: 1.52-3.66, p < .001), whereas ORs were not significant for primigravidity (OR = 1.40, 95% CI: 0.84-2.35, p = .192) nor for changing paternity (OR = 1.20, 95% CI: 0.49-3.10, p = .752). The risk was highest for multigravidas who had changed partners (OR = 8.71, 95% CI: 2.93-21.12, p < .001), followed by multigravidas who had not changed partners (OR = 3.99, 95% CI: 1.07-15.43, p = .049), and by primigravidas (OR = 3.02, 95% CI: 1.58-5.76, p = .001), all having cohabitated for a short time. Maternal age did not modify these risks.
  
  
  CONCLUSIONS
  Three groups at risk for a child with gastroschisis were identified, all having in common a short cohabitation time. Antigenic or "modern" lifestyle-related factors might be involved in the origin of gastroschisis.
authors.affiliation: Latin-American Collaborative Study of Congenital Malformations, WHO Collaborating Centre for the Prevention of Birth Defects (ECLAMC) at Hospital Materno Infantil Ramón Sardá, Buenos Aires, Argentina. mrittler@fibertel.com.ar
authors.forename: Monica
authors.initials: M
authors.lastname: Rittler
authors.forename: Eduardo E
authors.initials: EE
authors.lastname: Castilla
authors.forename: Christina
authors.initials: C
authors.lastname: Chambers
authors.forename: Jorge S
authors.initials: JS
authors.lastname: Lopez-Camelo
mesh_terms: D016022:Case-Control Studies; D005260:Female; D020139:Gastroschisis / Q000209:etiology*; D020073:Gravidity; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008423:Maternal Age; D010334:Paternity; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000209:etiology*; D012307:Risk Factors; D013997:Time Factors