Uterine septum can cause both infertility and recurrent pregnancy loss.
When the uterus is developing, it actually starts out as two separate organs located near each kidney. As fetal development occurs, these two segments fuse in the middle becoming a single uterus. The cavity of the uterus then starts to form from the bottom (the cervix) and develops upwards.
An abnormality in uterine development is called a Mullerian anomaly.
The most common Mullerian anomaly is the uterine septum. In this situation, the two developing immature uteri fuse in the midline. Unfortunately, however, the wall between these two structures fails to reabsorb, leaving a piece of tissue in the middle (the septum). This septum is made of thick muscle tissue and it does not have good enough blood flow to support a developing pregnancy. Therefore, early pregnancies either fail to attach to this septum or they are miscarried relatively early.
A uterine septum is typically easy to repair with surgery.
The surgical procedure is called a hysteroscopic metroplasty, and it is performed on an outpatient basis. Sometimes laparoscopic guidance is necessary in order to minimize surgical risk and enable a more complete removal of the septum. During the hysteroscopy, a small operative telescope is introduced vaginally into the uterine cavity. The septum is cut and the uterus is then much more likely to be able to accept implantation. Pregnancy is usually possible within 2-3 months after the procedure.
There are many other less common types of Mullerian abnormalities. These other uterine anomalies may significantly reduce a woman’s fertility as well as raise her risks for miscarriage and even cesarean section if she does conceive. Pregnancies that occur in women with Mullerian anomalies are typically high risk, as there is an increased likelihood of preterm labor, premature delivery, abnormal fetal presentation (anything other than a baby that comes down head first), and cesarean section. None of the abnormalities beside a uterine septum are repaired surgically because outcomes are not improved with surgery.
For more information please see this ASRM Guide:
Abnormalities of the Female Reproductive Tract (Müllerian Defects)
If you have any questions, please contact our San Antonio fertility center.