[The relationship between clinical diagnosis and placental findings in 561 placentae delivered less than 32 weeks' of gestation].

The relationship between clinical diagnosis and placental findings for 561 consecutive cases of delivery at 24 to 31 weeks' gestation were analyzed, and the following results were obtained. 1) The incidence of premature rupture of the membranes (PROM), threatened premature delivery, toxemia and abruption placentae were 40.6, 36.4, 7.8 and 3.0%, respectively. 2) The incidence of chorioamnionitis, retroplacental hematoma (RPH) and placental infarction were 35.1, 18.0, and 13.0%, respectively. 3) Chorioamnionitis of the placenta was found 58.3% in PROM and 26.0% of cases of threatened premature delivery. 4) RPH was found in 70.6% of placenta of abruption and 36.4% of toxemia. 5) Placental infarction was found in 86.4% of toxemia cases and 35.3% of abruption. Each clinical diagnosis was related specifically to each placental finding in cases delivered at 24 to 31 weeks of gestation.