O26: Maternal care for other conditions predominantly related to pregnancy

O26.4: Herpes gestationis

The first sign of this condition is red patches that form on the skin. The red patches can be flat or slightly higher than the surrounding skin. They may first appear around the belly button and later spread. Blisters filled with fluid may also form on the red patches.

The child can either not be affected or be born with a similar rash.

The exact cause of this condition is not yet known for sure. However, it is believed that the body’s immune system is involved. The immune system normally protects the body against pathogens and foreign substances. With some disorders, however, parts of the immune system target the body's own tissue or cells. It is believed that this condition causes the immune system to form antibodies against components of a person’s own skin.