Background: When the placenta detaches from the uterine wall prior to delivery, this condition is known as placental abruption. A placental abruption may cause the mother to bleed profusely and deprive the unborn child of oxygen and nourishment. Patients and methods: This Study included 72 singleton pregnant women with clinical and / or sonographic diagnosis of placental abruption, 44 cases were preterm gestations and 28 were term gestations and their matched controls, who all attended the labor ward in Al-Yarmouk Teaching Hospital, Department of Obstetrics and Gynecology during the study period. After delivery, all study population were submitted for histologic examination of their placentae. Each placenta was reviewed for gross findings and histologic evidence of chorioamnionitis. The degree of chorioamniontis is then sub- classified into mild, moderate or severe. The association between histologic chorioamnionitis and placental abruption were analyzed in all groups. Results :first trimester body mass index (BMI), there was a statistical difference in both preterm and term groups, and a mean ± SD of  26.9 ± 4.5, 24.2 ± 4.2 for preterm cases, Premature rupture of membrane approached statistical significance for preterm gestation with a higher incidence in cases (25%) than controls , the association between histological chorioamnionitis and placental abruption at preterm gestations OR 7.15, 95% CI (2.55-20.49) was significant. ,  PROM was more frequent in abruption cases as the severity of chorioamnionitis increased, with PROM presented in 71.4% of abruption cases with severe chorioamnionitis. Among abruption cases there was an apparent trend for earlier delivery in PROM group in comparison with non PROM cases, which was more striking with severe chorioamnionitis. Conclusion: Premature rupture of membrane approached statistical significance for preterm gestation with a higher incidence in cases than control, PROM was more frequent in abruption cases as the severity of chorioamnionitis increased, with PROM presented in abruption cases with severe chorioamnionitis.

Keywords: PROM; gestational age; delivery; chorioamnionitis; placental abruption