First Trimester Bleeding clinical trials

Early Pregnancy Evaluation by Three-Dimensional Ultrasound

Early pregnancy is associated with numerous physiologic alterations - many of which are required to establish normal pregnancy outcome. Three-dimensional ultrasound may provide new opportunities to better characterize some of these early changes. This noninvasive method allows one to arbitrarily scan through a digital ultrasound volume data, visualize organs from different perspectives, and render anatomical features through computer processing. Retrospective measurement of distances and volumes are even possible in the physical absence of the patient. New information provided by three-dimensional ultrasound may lead to improved understanding about how to counsel parents regarding early pregnancy complications such as bleeding. For example, vaginal bleeding complicates approximately 15-20% of first trimester pregnancies. A common association is subchorionic hemorrhage which is associated with increased risk for miscarriage, preterm delivery, preterm premature rupture of membranes, stillbirth, and placental abruption. Several studies have attempted to characterize subchorionic hemorrhage by conventional two-dimensional ultrasound which is not particularly well-suited for accurate measurement of small irregular hematomas. Consequently, there has been considerable debate about the significance of this finding especially in asymptomatic women who undergo prenatal ultrasound examination for other reasons. This protocol will attempt to identify prognostic indicators of adverse pregnancy outcome. A maximum of 400 pregnant women up to 20 weeks' gestation with sonographically detected subchorionic hemorrhage will be serially studies to characterize sac volume, placental volume, hematoma volume, and placental blood vessel patterns by 3DUS techniques. These results will be correlated with pregnancy outcome, hormonal markers, and placental pathology. This information is expected to improve our understanding of the natural history of subchorionic bleeding and spontaneous miscarriages as well as prognostic factors influencing pregnancy outcome in both symptomatic and asymptomatic women.