Blood clots that form in the uterus are called subchorionic hematomas or subchorionic hemorrhage. These words sound frightening, but they describe a condition that's actually quite common in early pregnancy. Subchorionic hematomas or subchorionic hemorrhage are simply areas of coagulated blood located between the uterine wall and the gestational sac of the developing fetus.
Frequency
Doctors are discovering that blood clots in the uterus during early pregnancy are much more common than previously thought. Many of these cases would never have been identified in past years. As first trimester ultrasound imaging has become more routine, more doctors are detecting these early blood clots. Some studies have observed blood clots in up to 48 percent of pregnancies, says an article in the "Obstetrical and Gynecological Survey."
Causes
Most subchorionic hematomas are caused by a ruptured blood vessel in the wall of the uterus. This can occur during implantation or as a result of other normal activity. The good news is that most of these first trimester blood clots will dissolve within a few weeks without any additional treatment. Some women with small blood clots will continue to experience periodic light vaginal bleeding throughout their pregnancy. While these bleeding episodes may be stressful and scary, they often have no ill effects on the developing fetus, according to the What To Expect website.
Less often, blood clots may be the result of a partial placental abruption. This means that the placenta, the organ that provides the developing baby with oxygen, nutrients and fluids, starts to peel away from the wall of the uterus. When this occurs, blood may pool behind the placenta and form a blood clot. A small separation is usually not harmful and may resolve on its own. However, if the separation increases as the pregnancy progress, it can affect the flow of oxygen and nutrients to the baby. According the the Mayo Clinic, complete placental abruption is a rare but serious condition that requires immediate medical attention. A woman should seek immediate medical attention if vaginal bleeding becomes more severe or is accompanied by cramping and abdominal pain.
Symptoms
Some women may experience vaginal bleeding in early pregnancy or may not have any symptoms at all. Many symptomless subchorionic hematomas are first identified during a routine first trimester ultrasound, notes What To Expect.
Diagnosis
If there is vaginal bleeding, the doctor will order a sonogram to visualize the placenta, uterus and developing baby. Ultrasound imaging is safe for the baby and does not expose him to dangerous radiation.
Treatment
A doctor may advise a mother-to-be to rest and take it easy for a period of time. She should avoid heavy lifting and high-impact exercise. Depending on the severity and size of the clot, she may be placed on bed rest or pelvic rest, which means avoiding intercourse and other sexual activities. The What to Expect website says a doctor will ask her to return for a follow-up ultrasound within a few weeks to determine whether the size of the blood clot is decreasing.
