Subchorionic Hematoma and Pregnancy

A Hematoma is a localized collection of blood, or clotting, which occurs outside the blood vessels in a tissue or organ. Subchorionic hematoma is the gathering of blood between the membranes of the placenta and the uterus. Subchorionic hematoma usually manifests itself in the early stages of pregnancy. With the help of ultrasound technology, it is easier to detect a subchorionic hematoma. The clot appears as a black mass within the uterus.

In women with subchorionic hematoma, the outcome depends on the size of the hematoma, the mother’s age, and the fetus’s age. If it is small or moderate in size, the subchorionic hematoma often regresses. The clot either bleeds itself out or the body absorbs it. However, if the hematoma is large in size, it strips away at least 30% to 40% of the placenta away from the endometrium. If it goes undetected and continues to grow, it may lead to a premature rupture of the membranes. It can also release completely from the uterus and cause the fetus and placenta to miscarry.

There is no known cause for a subchorionic hematoma but sometimes during egg implantation, the egg might slightly separate from the uterus causing a bleed. There is no prevention for this and women of all ages and races can be affected by this condition.

Most patients with a small subchorionic hematoma are asymptomatic. Common manifestations in the first and second trimester include vaginal bleeding, abdominal pain and premature labor. Vaginal bleeding is the most common symptom of subchorionic hematoma. Thus, if you are experiencing vaginal bleeding in the early months of your pregnancy, getting an ultrasound is highly advisable. However, as the blood passes vaginally, it might sometimes not collect in the subchorionic space. If this is the case, then the hematoma is small and should not pose a threat.

Symptoms of subchorionic hematoma in the latter stages of pregnancy are more severe and tend to include a painful and tense uterus and fetal distress. There is no formal treatment for subchorionic hematoma. However, blood thinners such as aspirin are commonly used to attempt to bleed the clot out. Anti-coagulants are sometimes used for this as well. Women with subchorionic hematoma can also be given extra estrogen and progesterone to aid in the development of the fetus.

Straining and heavy lifting should be avoided, as is the case for a normal pregnancy. While some doctors might advise to you to rest, others might suggest carrying on with everyday activities. Some physicians might even suggest refraining from sexual intercourse during the length of the pregnancy.