What Causes Congenital Vaginal Obstruction?

The most common cause is an imperforate hymen. This means the tissue that makes the hymen fails to split and leave a hole. In this case the area stays covered.

Less often (1 in 70,000) it is from a high transverse septum. This is when the vagina does not develop fully.

Either of these issues can lead to swelling of the vagina and uterus.