Labial fusion
Overview
Labial fusion, or labial adhesion, is when the small inner lips around the entrance to the vagina become sealed together.
Causes
It's not certain what causes labial fusion, but it may happen as a result of irritation or inflammation of the vaginal area, known as vaginitis. This can cause the inner lips of the vulva to become sticky. Without enough oestrogen in the body, which is quite normal before puberty, the lips can stay stuck together and gradually become firmly joined. The problem is rarely seen in girls after they begin puberty because this is when they start to produce the hormone oestrogen. Labial fusion can also sometimes happen after childbirth or after the menopause, when oestrogen levels are also low.