In addition to the two main categories of pemphigoid, Pemphigoid Gestationis is a rare pregnancy-associated autoimmune skin disease that is characterised by an itchy rash that develops into blisters. It is most common during the second and third trimesters of pregnancy.

Most patients present with an intensely itchy hive-like rash during mid to late pregnancy (13 to 40 weeks gestation).

• Initially, there are itchy red bumps around the belly button

• Within days to weeks, the rash spreads to other parts of the body including the trunk, back, buttock, and arms. The face, scalp, palms, soles and mucous membranes are usually not affected.

• After 2-4 weeks, large, tense fluid-filled blisters form

• Some patients may have no blisters but instead, have large raised patches.

In some cases, pemphigoid gestationis occurs throughout pregnancy. Symptoms may lessen or spontaneously resolve towards the end of the pregnancy but this is short-lived, as 75-80% of women will experience a flare-up around delivery. In most cases, symptoms resolve days later after giving birth, however, in some, the disease remains active for months or years. Commencement of menstrual periods, use of oral contraceptives or further pregnancies may cause flare-ups, but, in most cases, pemphigoid gestationis resolves spontaneously within days after delivery so treatment can be tapered off and stopped.

Further information can be obtained at the sites suggested below.

https://www.skinhealthinfo.org.uk/condition/pemphigoid-herpes-gestationis/

https://dermnetnz.org/topics/pemphigoid-gestationis/