The frequency and severity of placental findings in women with preeclampsia are gestational age dependent

OBJECTIVE: The purpose of this study was to evaluate placental lesions found in women with preeclampsia compared with normotensive control subjects and to determine whether the presence of these lesions are related to gestational age at delivery. STUDY DESIGN: Placental disease of women with preeclampsia at 24 to 42 weeks of gestation was compared with the placental disease of normotensive gestational age-matched control subjects. The placental lesions that were studied specifically included decidual arteriolopathy, thrombi in the fetal circulation, central infarction, intervillous thrombi, and hypermaturity of villi. Data analysis involved the chi(2) test, the Student t test, and logistic regression; odds ratios and Cls were estimated. RESULTS: Placentas from women with preeclampsia (n = 158) and normotensive control subjects (n = 156) were evaluated. Among women with preeclampsia, 67% had severe disease. Placental lesions were studied according to gestational age at delivery: < 28, 28 to 32, 33 to 36, and -37 weeks of gestation. Of the placental lesions that were studied, decidual arteriolopathy (odds ratio, 23.8, 95% Cl 10.0-57.0), hypermaturity of villi (odds ratio, 12.4; 95% Cl 5.3-29.2), intervillous thrombi (odds ratio, 1.95;95% Cl 1.0-3.7), central infarction (odds ratio, 5.9; 95% Cl 3.1-11.1), and thrombi in the fetal circulation (odds ratio, 2.8; 95% Cl 1.2-6.6) were found to have significantly higher rates in the preeclamptic group. In contrast, the rate of chorioamnionitis was significantly lower in the preeclamptic group (odds ratio, 0.2; 95% Cl 0.1-0.4). The rates of abruptio placentae and meconium staining were not different between the two groups. Within the preeclamptic group, the rates of decidual arteriolopathy (P<.0001), central infarction (P =.0001), and hypermaturity of villi (P<.0001) were higher the earlier the gestational age at delivery. CONCLUSION: Placentas in women with preeclampsia have increased amounts of disease. The rate is increased with lower gestational ages at the time of delivery for women with preeclampsia.