Distribution of placental grade in high-risk gravidas.

One hundred twenty-eight high-risk gravidas and 62 normal gravidas who had undergone placental sonography were compared retrospectively according to placental grade, risk category, and stage of pregnancy at the time of the examination. Pregnancies ranged from 28 weeks of gestation to term. For analysis, the group of high-risk patients was subdivided into four categories representing specific disease states: chronic hypertension and/or preeclampsia, intrauterine growth retardation, maternal diabetes, and Rh sensitization. To eliminate gestational age bias, both the normal group and the high-risk subgroups were further subdivided into preterm and term pregnancies. Placental grade distribution was similar between the high-risk group overall and the normal group, but specific disease entities were associated with widely varying distributions of placental grade. In particular, hypertension and intrauterine growth retardation showed a strong correlation with accelerated placental maturation, whereas diabetes and Rh sensitization were associated with delayed maturation of the placenta. These differences were more pronounced in the preterm population.