title: Maternal and neonatal interleukin-1 receptor antagonist genotype and pregnancy outcome in a population with a high rate of pre-term birth.
abstract: OBJECTIVE
  We evaluated associations between a length polymorphism in intron 2 of the gene coding for IL-1ra (gene symbol IL1RN) and pregnancy outcome in a population with a high rate of preterm birth.
  
  
  METHODS
  Subjects were pregnant women in Maceio, Brazil and their newborns. DNA was tested for IL1RN genotypes and alleles by gene amplification using primer pairs that spanned the polymorphic region. Every subject completed a detailed questionnaire.
  
  
  RESULTS
  The frequency of allele 2 (IL1RN*2) carriage was elevated in mothers with a spontaneous preterm birth (SPTB) in the current pregnancy (P = 0.02) and also with a prior preterm delivery (P = .01). Both SPTB with intact membranes (P = 0.01) and SPTB preceded by pre-term premature rupture of membranes (P = .03) were associated with ILlRN*2 carriage. A previous fetal demise was more than twice as prevalent in mothers positive for two copies of IL1RN*2.
  
  
  CONCLUSIONS
  Maternal carriage of ILlRN*2 increases susceptibility to inflammation-triggered spontaneous pre-term birth.
authors.affiliation: Universidade Estadual de Ciências da Saúde de Alagoas, Maceio, Brazil.
authors.forename: José Humberto Belmino
authors.initials: JH
authors.lastname: Chaves
authors.forename: Arthur
authors.initials: A
authors.lastname: Babayan
authors.forename: Cledna de Melo
authors.initials: Cde M
authors.lastname: Bezerra
authors.forename: Iara M
authors.initials: IM
authors.lastname: Linhares
authors.forename: Steven S
authors.initials: SS
authors.lastname: Witkin