What Does
Subchorionic Hemorrhage (SCH) Mean?
Subchorionic hemorrhage (SCH) is thought to occur when you get tearing of the vessels between the lining of the uterus and the chorionic membrane of the pregnancy, causing blood to pool between the placenta and the wall of the uterus. The blood then vacates the uterus through the vagina, causing the vaginal bleeding.
The level of risk for the mother and fetus depends on the size of the hematoma and the severity of the bleeding, and may require medical treatment.
Studies are conflicting on whether SCH leads to miscarriage with some showing no increased risk of miscarriage and others showing a slightly increasedrisk.
A subchorionic hemorrhage is also called a subchorionic hematoma or subchorionic bleeding.
FertilitySmarts Explains Subchorionic Hemorrhage (SCH)
The chorion is the outermost membrane that separates the embryo from the mother’s endometrium. It provides a layer of protection and facilitates the exchange of nutrients between the mother and embryo.
The chorion will develop chorionic villi that are finger-like projections that connect to the maternal blood supply though the endometrium and become part of the placenta.
When the placenta is disrupted, the bleeding impacts this layer of membranes, causing blood to pool. It is thought that this may be the cause of SCH.
In many cases of SCH there is no vaginal bleeding, and the condition is typically asymptomatic. It may not be discovered until a medical professional spot it during a routine ultrasound.
When does a subchorionic bleed happen?
This type of bleeding is more common in the first trimester of pregnancy, and less common in the second or third.
Risk Factors
Bleeding in early pregnancy occurs in about 15-25% of pregnancies. Estimates of between 1% and 22% of pregnancies are impacted by a subchorionic bleed.
In vitro fertilization (IVF) is a risk factor. SCH appears more frequently in pregnancies conceived through IVF and may have a higher incidence in women who take baby aspirin in early pregnancy.
SCH or Miscarriage?
Bleeding during pregnancy is often unexpected and alarming. In cases where vaginal bleeding is more pronounced with a heavy flow, it is possible to confuse a SCH with a miscarriage.
An ultrasound can easily detect and diagnose the clot causing the SCH and rule out miscarriage.
Outlook
The prognosis for a SCH depends on the severity and extent of the bleeding. Smaller hematomas found earlier in the pregnancy usually resolve on their own and do not lead to adverse outcomes, while larger hematomas may increase the risk of miscarriage or second-trimester complications and they may require treatment, including:
- Pelvic rest
- Avoiding sex
- Avoiding exercise
- Taking hormonal medication
Women diagnosed with SCH will be monitored carefully by their physician until the bleeding subsides.