Uterine septum is the most common uterine congenital anomaly. A condition is said to be a congenital anomaly when it affects a person from birth. In this condition extra tissue called the septum hangs in the uterus from the top. The septum is often shaped like a wedge and maybe small or may hang from the top to the cervix (mouth of the uterus) , thereby dividing the uterus into two cavities.
The extra tissue which is formed is unlike the tissue which makes up the rest of the uterus this is because it has poor blood circulation. Hence, a fertilized egg (embryo) can’t implant itself in the uterus and even if it does manage to it may fail to develop further. Therefore, uterine septum can lead to infertility.