TGFB1 and chorioamnionitis: Although the frequency of the common TNFRSF6-1377 G/G genotype was higher in women with histologic chorioamnionitis (0.87 versus 0.73, OR 2.4, P = 0.03), the variant TNFRSF6-1377A/-670G (AG) haplotype (OR 0.4, P = 0.03) and homozygosity for the TGFB1 haplotype -800G/-509T (GT) (OR 0.2, P = 0.03) were negatively associated with chorioamnionitis (Table 2).