We see subchorionic hematomas or suspect subchorionic clots in perhaps 1% of pregnancies in the between 13 and 22 weeks. Most of these occur in women who have had vaginal bleeding.

How long does a Subchorionic hemorrhage last?

A subchorionic hematoma can be considered large if it is greater than 50% of the size of the gestation sac, medium if it is 20-50%, and small if it is less than 20%. Large hematomas by size (>30-50%) and volume (>50 mL) worsen the patient's prognosis. Hematomas may resolve over 1-2 weeks.

Does a Subchorionic hemorrhage go away?

In most cases, the bleeding goes away on its own. Most women go on to have a healthy baby. But in some cases, the bleeding is a sign of a miscarriage or other problem with the pregnancy. Your doctor may want to do a follow-up ultrasound.