The Impact of Incidental Ultrasound Finding of Subchorionic and Retroplacental Hematoma in Early Pregnancy.

BACKGROUND: Chorionic hematomas can be caused by the separation of the chorion from the endometrium, with an incidence of 3.1% of all pregnancies. It is the most common sonographic abnormality and the most common cause of first-trimester bleeding.

OBJECTIVES: To evaluate the impact of subchorionic and retroplacental hematomas detected by ultrasound in the first trimester of pregnancy.

PATIENTS AND METHODS: A prospective observational case-control study was conducted at Elwiya Maternity Teaching Hospital on 100 pregnant ladies with subchorionic or retroplacental hematoma shown in ultrasound compared with 200 pregnant ladies without hematoma in the first trimester. The demographic feature, course of pregnancy, obstetric outcome, and neonatal outcome were analyzed.

RESULTS: There was statistically significant difference between both groups regarding maternal and neonatal outcome. In regard to maternal outcome, there is increasing rate of miscarriage (20%, P  = 0.004), preterm labor (18%, P  = 0.005), intrauterine growth restriction (7%, P  < 0.001), abruption (9%, P  = 0.001), and cesarean section (60%, P  < 0.001) compared to control group. Regarding neonatal outcome, there is increasing rate of low gestational age at birth ( P  = 0.004), low birth weight ( P  = 0.003), low Apgar score at 1 & 5 min ( P  < 0.001, P  = 0.002, respectively), and more admission to NICU ( P  = 0.015) in study group when compared to control group.

CONCLUSION: The presence and the characteristic of an intrauterine hematoma during the first trimester may identify a population of patients at increased risk of adverse pregnancy outcome as miscarriage, preterm delivery, IUGR, abruption, low birth weight, cesarean section rate, low Apgar score at 1 and 5 min, and NICU admissions in patients with intrauterine hematoma.The miscarriage rate with retroplacental hematoma is significantly higher than with subchorionic hematoma. The size of the hematoma is significantly greater in the miscarriage group.All subchorionic hematomas disappeared, but 2% of retroplacental hematomas did not disappear until the end of second trimester.