Objective: Two single-base polymorphisms of the tumor necrosis factor-alpha gene (TNF-alpha) at positions -863 and -308 are associated with variation in production of TNF-alpha (TNF-alpha). TNF-alpha genotypes were tested for association with adverse outcomes in mother-infant pairs with preterm labor.
Study design: We analyzed a cohort of 118 mother-infant pairs with preterm labor before 34 weeks' gestation. Polymerase chain reaction was used on extracted deoxyribonucleic acid for polymorphism assay. Outcomes included amniotic fluid TNF-alpha concentration, histologic chorioamnionitis, delivery gestational age, and composite neonatal morbidity. Statistical significance was determined by chi 2 and Kruskal-Wallis analysis of variance.
Results: Mothers homozygous for the -863 polymorphism (AA) had significantly earlier deliveries ( P = .02), more chorioamnionitis ( P = .03), and greater composite neonatal morbidity ( P = .03). Neither maternal nor fetal carriage of the -308 polymorphism was associated with adverse outcome.
Conclusion: In women with preterm labor before 34 weeks' gestation, maternal homozygous carriage of the -863 polymorphism may be associated with preterm delivery and adverse neonatal outcome.