SubChorionic Haemorrhage

Carrying another life within you is a joyous experience, but also calls for a lot of responsibilities. Theoretically, there can be no reason for bleeding during pregnancy. However, this phenomenon is not uncommon, and not all types of bleeding are fatal. With advancement in medical science, the days when doctors would consider bleeding in a pregnant woman as a sign of imminent miscarriage during the early days are long gone. With the advent of ultrasound technology, doctors can now delve deeper into the diagnosis of the problem.


However, as a would-be mother, you need to be alert to avoid delays and undergo necessary treatment on time, in consultation with your gynaecologist if the bleeding is serious.


What is Sub-Chorionic Haemorrhage?

Chorion is the external layer that encloses the embryo which develops as a foetus. This membrane is placed between the uterus and the placenta. If for any reason the placenta gets detached from the original site of implantation, the chorionic membranes get lifted apart and forms a sac in between the placenta and the uterus. These movements may result into bleeding and blood gets collected in the chorion, resulting in a sub-chorionic haemorrhage. A sub-chorionic haemorrhage is also known as sub-chorionic hematoma or, sub-chorionic bleeding.

A sub-chorionic haemorrhage can have variable sizes from small to large clots. The smaller ones are more prevalent and result in spotting while the larger ones lead to excessive bleeding. Usually, sub-chorionic haemorrhage resolves naturally and you can still have a healthy pregnancy.

How Common is Sub-Chorionic Haematoma?

This is a very common anomaly detected through ultrasound, especially observed during the first trimester of pregnancy. Almost 22 to 25 out of every 100 women experience vaginal bleeding during the first half of pregnancy.

Women undergoing infertility treatment through in vitro fertilization (IVF) are more prone to sub-chorionic hematoma by 22.4% in comparison to those undergoing the treatment through non-IVF methods that shows a statistic of 11% (Asato et al., 2014).

How is Sub-Chorionic Bleeding Different From Other Bleeding Types?

A sub-chorionic haemorrhage should not be mistaken for spotting. Spotting, as the name suggests is an accumulation of a few spots of blood. Within 12 weeks of pregnancy, around 20% of women experience spotting. However, sub-chorionic haemorrhage results in bleeding and spotting. Women experiencing it may need to wear panty liners. Serious vaginal bleeding may be accompanied by severe abdominal pain ordizziness.


The real causes of sub-chorionic haemorrhage are still unknown. However, following are considered to be the possible triggers:

  • A concern with the egg implantation process where the egg gets implanted in the uterus lining may lead to cramping pain and bleeding
  • In case a mother’s abdomen gets subjected to extreme trauma due to some accident, it may result in a haemmorhage
  • Blood coagulation during pregnancy
  • Drug usage by the mother during early pregnancy
  • Scars resulting from dilation and curettage (D&C) procedure post-abortion or, miscarriage
  • In case the mother’s age is above 35 years

Is Sub-Chorionic Hematoma Harmful During Pregnancy?

Usually, sub-chorionic hematomas get dissolved naturally. However, sometimes the placenta might get detached from the uterus which increases the chances of pre-term labour or miscarriage. The probability of miscarriage increases with the increase in age of the would-be mother and with the increase in the size of the hematoma.

A sub-chorionic hematoma towards the end of the first trimester or early second trimester can fractionally tear away the developing placenta from its site of attachment. Large hematomas can tear away up to 40% of the placenta from the endometrium, and can grow larger in size, thereby applying pressure on the gestational area and rupture the membrane and lead to abortion. Sub-chorionic hematomas occurring beneath or, at the edge of the placenta or, behind an isolated area of the foetal membrane can be a cause of concern. Large intrauterine hematomas can restrict the growth of the foetus and also hamper the mother’s health.


  • When the hematomas are very small there may be no symptoms at all. Such hematomas are detected only through ultrasound.
  • Spotting
  • Vaginal bleeding with or without mild cramping.


Sub-chorionic bleeding can be diagnosed through sonography. The procedure can be easily performed at the bedside of the patient and there is no known risk owing to the radiations.

Regular subchorionic haemorrhage ultrasound, either transvaginal (the imaging process is initiated at the vagina to examine the uterine area) or abdominal show the blood clots as a black mass within the uterus. From appearance, it seems as though a second placenta is present. With the help of the images of the bones, a regular sonography appears blackish. Post identification of the blood clots, the sub-chorionic haemorrhage can get diagnosed.

The ultrasound provides clarity regarding the size and position of the clot, the actual amount of bleeding and the site of the collection of the blood. It also shows whether placenta has been subjected to damage as well as the extent of damage.

Whether the clots are resolving naturally or continue to grow further may be determines with the help of follow up ultrasounds.

Risks & complications

  • The placenta can get detached from the uterine wall posing the risk of pre-term birth or miscarriage.
  • Risk of miscarriage depends on the extent of bleeding owing to the sub-chorionic hematoma.
  • In the presence of other complications during pregnancy, sub-chorionic haemorrhage can pose life risk for the foetus.


  • Bed rest
  • Refraining from sexual intercourse
  • Refraining from physical strain such as lifting heavy weights, vigorous walking, standing for long periods
  • Progesterone or, oestrogen therapy. Dydrogesterone is an artificial progesterone hormone which can be taken orally to treat sub-chorionic haemorrhage.
  • Blood thinners such as Lovenox (inj), aspirin, Heparin (inj) and Coumadin are often prescribed to remove the clots.
  • A follow-up examination is necessary to detect the change in the size of the hematoma and accordingly plan further treatment.
  • Consuming adequate water to avoid cramps from dehydration.
  • Eating regular small meals to avoid cramps from hunger.

Managing Sub-Chorionic Haemorrhage

Sub-chorionic haemorrhage calls for extra precautions to be taken by the mother. Here are a few tips to help manage it:

  • Mothers can increase the intake of fibre and water to avoid constipation so as to avoid physical stress during excretion.

  • Adequate rest can assist in healing injuries and reduce heart rate. Physical stress needs to be avoided.
  • Regular ultrasounds along with regular doctor visits can help in understanding the status of the hematoma.

When Should You Call The Doctor?

As sub-chorionic haemorrhage may mild symptoms, which sometimes may not be clearly noticeable, , it is suggested that you visit the doctor at least bi-weekly during the first trimester for screening tests. You must also go for the routine ultrasounds as they may help in the timely detection of clots in case there are any. If there is any bleeding or spotting, do consult your doctor to identify and address the issue immediately.

Thus, sub-chorionic haemorrhage could prove to be fatal for the baby if it is not detected or diagnosed in time. If you experience any bleeding in pregnancy, ensure that you consult your doctor to identify the issue, and take the necessary precautions to ensure a healthy pregnancy and a safe delivery.