Chorioamnionitis in relation to gestational outcome in a Swedish population.

In a histopathological study, from a homogeneous Swedish population with a better than average socio-economic standard, placentas from 161 singleton infants small for gestational age (SGA) and 322 singleton infants appropriate for gestational age (AGA) were examined for the presence of inflammation in the placental parenchymal membranes, cord and decidua. Acute chorioamnionitis including funiculitis was found in 13.4% of the total material, in 17% of term AGA-infants (GA, greater than or equal to 38 weeks), in 13% of preterm AGA-infants (less than or equal to 37 weeks) and in 6.8% of SGA-infants (p less than 0.001, compared to term AGA). Acute chorioamnionitis was correlated to vaginal delivery (p less than 0.01), rupture of the membranes greater than 24 hours (p less than 0.01), nulliparity (p less than 0.05) and amniocentesis (RR = 1.7). In nulliparous, chorioamnionitis was related to duration of labor greater than 16 hours (p less than 0.01). Streptococcal (p less than 0.01) and anaerobic vaginal infections (p less than 0.05) were also related to chorioamnionitis. Of 17 infants with sepsis, 6 had chorioamnionitis (p less than 0.05). Decidual inflammation was chronic in type and found in 4.5% of the placentas and was not related to chorioamnionitis, but to parity (p less than 0.05) and term AGA-infants (p less than 0.001).