Septate Uterus: What You Need to Know

A septate uterus is a congenital condition in which a thin membrane called a septum divides the uterus, either partially or completely. The condition is rare, though it's one of the more common uterine abnormalities. Many who have septate uteri are unaware they are living with them, and while the condition does not affect a person's ability to conceive, it can impact a pregnancy's outcome.

"We see a higher risk of first- and second-trimester pregnancy loss with septate uterus," says Beth W. Rackow, M.D., an assistant professor of OB-GYN at Yale University School of Medicine in New Haven, Conn. "There is also an increased risk of preterm labor."

What Is a Septate Uterus?

A septate uterus is a deformity of the uterus, one which usually happens during fetal development. The shape of a septate uterus is normal, as are other features; however, the uterus divides into two separate cavities.

How Does a Septate Uterus Affect Pregnancy?

While a septate uterus does not affect a person's ability to conceive, the condition may make it harder to carry a pregnancy to term, i.e. having a septate uterus significantly increase your risk of miscarriage. Those with septate uteri have a pregnancy loss rate of 20 to 25%, and recurrent miscarriages are also common.

What Causes a Septate Uterus?

Unfortunately, the cause of septate uteri is unknown. The condition is a genetic abnormality—that much is clear—but the exact reason why it occurs is unclear.

What Are the Symptoms of a Septate Uterus?

In most cases, there are no symptoms of a septate uterus. Rather, the condition is diagnosed after a miscarriage. However, some people will experience unusual pain before and/or during menstruation or excessive bleeding.

How Is a Septate Uterus Treated?

Luckily, a septate uterus can be treated before pregnancy with a minor procedure called a hysteroscopy. "This involves inserting surgical instruments through the cervix and removing the septum without having to make an abdominal incision," Rackow explains. It's usually done on an outpatient basis.

Septate uterus is the most common congenital uterine malformation, affecting 1% of all people. Because there are varying degrees of severity, "Not everyone needs to be treated," Rackow says. "If you do, it's comforting to know that this is the only congenital uterine anomaly that can be fixed with a minimally invasive procedure, thereby improving reproductive outcomes."