Gestational Pemphigoid (Pemphigoid Gestationis)

Pemphigoid gestationis is an autoimmune disorder of the second and third trimester of pregnancy. It is characterised by itchy blisters which start on the abdomen before spreading to other body parts. Symptoms worsen during the third trimester and improve postpartum before resolving completely within weeks to months following delivery. There is an increased risk of preterm labour, small-for-gestational-age infants, transient neonatal bleeding, and autoimmune diseases – such as Graves’ disease or Hashimoto’s thyroiditis- in patients with pemphigoid gestationis.

The aetiology is unknown, but it is most likely immunological. BP180 protein – which is identified in bullous pemphigoid – is found in the placenta, possibly explaining disease onset in pregnancy.

• Signs and symptoms
  • Pruritic erythematous macules, papules and urticarial plaques
    • Abdominal – particularly periumbilical
    • Spreads centrifugally to involve the trunk, extremities, buttocks, face and scalp
  • Evolve into tense vesicles and bullae
    • Filled with clear fluid or serosanguinous exudate
    • Rupture easily
  • Mucosal lesions may be present
  • Grouped vesicles with herpetiform appearance may occur as the disease advances (‘Gestational herpes’)
  • May present with atypical features such as: targetoid lesions, annular erythematous plaques, or vesicles on an erythematous base
• Differentials
  • Pustular psoriasis of pregnancy
  • Polymorphic eruption of pregnancy
  • Bullous pemphigoid
  • Epidermolysis bullosa acquisita
• Investigations
  • Skin biopsy and Immunofluorescence to confirm the diagnosis
• Treatment
  • Usually self-limiting and heals after delivery spontaneously
  • Carry out treatment with care to reduce side effects to both mother and fetus
    • Minimum effective doses of steroids
    • Avoid immunosuppressive treatment until the postpartum period
• Complications
  • Premature labour
  • Increased lifetime risk of developing autoimmune disease
  • An infant may develop transient blistering after birth (resolves spontaneously)
• Recurrence
  • Spontaneously during the postpartum period
  • When using some hormonal contraceptives
  • During menstruation
  • In subsequent pregnancies