RESUMEN
We carried out a retrospective study on 96 patients whose uterine waveforms were abnormal, in order to determine if a laterally located placenta further increased this risk. Our population was separated into 2 groups (75 women with a laterally located placenta, 21 with a centrally located placenta). We have found a significant difference between ipsi placental uterine blood flow velocity and contralateral placental blood flow velocity when the placenta is located laterally, where as the 2 arteries are similar when the placenta has a central location. The following factors were used to compare the two groups: the patient's previous obstetric record and the incidence of hypertensive disorders and fetal distress. In the group with laterally located placentas, the incidence of complications in previous pregnancies was higher, hypertension was more frequently serious or presented complications, fetal distress and cesarean sections were more frequent as was IUGR. All cases of intrauterine death were found in the group with laterally located placentas. In determining the predictive value of the "laterally located placenta" test, we found in the centrally located placenta group that hypertensive disorders were often less serious and less frequently complicated by albuminuria, that the outcome of pregnancy disorders was less serious for the fetus, and that the neonate was less hypotrophic. No incidence of intrauterine death was recorded for the centrally located group. Placental laterality significantly increases both the frequency and the seriousness of fetomaternal hypertensive disorders.