Interleukin-4 and -10 gene polymorphisms and spontaneous preterm birth in multifetal gestations.

The purpose of this study was to determine the relationship between maternal and fetal carriage of different alleles of interleukin-4 and -10 genes and pregnancy outcome in multifetal gestations. Buccal swabs from mother-infant pairs of 73 multifetal gestations were assayed for polymorphisms at position -590 of the interleukin-4 gene and position -1082 of the interleukin-10 gene. Pregnancy outcome data were obtained subsequently. Spontaneous preterm birth occurred in 29 of the pregnancies (39.7%). A higher frequency of the interleukin-4 T allele was found among mothers with spontaneous preterm birth compared with mothers without spontaneous preterm birth (36.2% vs 18.2%; P=.02; odds ratio, 2.6; 95% CI, 1.1-5.9). Moreover, 20.7% of mothers who had spontaneous preterm birth were homozygous for the interleukin-4 T allele, as opposed to only 2.3% of mothers who did not have a spontaneous preterm birth (P=.01; odds ratio, 11.2; 95% CI, 1.2-69.5). Similarly, in 55.2% of the pregnancies that were complicated by spontaneous preterm birth, 2 fetuses carried the interleukin-4 T allele, compared with only 29.5% of the pregnancies that were not complicated by spontaneous preterm birth (p<.05; odds ratio, 2.9; 95% CI, 1.0-8.8). There was no relationship between mother and infant IL-10 genotype and spontaneous preterm birth. Maternal and fetal carriage of the interleukin-4 T allele is associated with an increased risk of spontaneous preterm birth in multifetal gestations.