Subchorionic Hematoma: Correlation of Grading Techniques With First-Trimester Pregnancy Outcome

(Abstracted from J Ultrasound Med 2018;37:1725–1732) A common finding on early first-trimester ultrasound (US) examinations, subchorionic hematoma (SCH) occurs in both asymptomatic patients and those presenting with vaginal bleeding. Previous studies assessing the risk of first-trimester pregnancy failure when an SCH is seen on an early pregnancy sonogram have used a variety of grading systems for characterizing the size of the hematoma, including subjective grading of the SCH as small, moderate, or large; calculating the volume of the SCH from its US measurements; estimation of hematoma size as a fraction of gestational sac size; and estimated fraction of the gestational sac that is surrounded by hematoma.