Chorioamnionitis and funiculitis in the placentas of 200 births weighing less than 2.5 kg.

A retrospective histopathological study of the placental and non-placental membranes and umbilical cords of 200 live and stillborn babies weighing less than 2.5 kg is reported. The pathological studies were specifically concerned with the presence of infection as evidenced by a polymorphonuclear leucocytic infiltrate at these sites. Inflammatory lesions were demonstrated in 48.5% of specimens. The incidence of inflammatory lesions was highest in those with prolonged rupture of the membranes, and in the placentas of the smallest and least mature infants of a size appropriate to their gestational age. Puerperal pyrexia, neonatal sepsis and perinatal mortality were also more common in the infected group but none of the perinatal deaths was directly attributable to infection. The role of infection as a cause of premature rupture of the membranes, premature labour and subsequent perinatal outcome is still unclear though our data would suggest it is not unimportant.