Skin problems in pregnancy
Pregnancy may result in an increase in prevalence or severity of some common skin problems. These include:
- Atopic dermatitis and psoriasis (may also improve, or remit)
- Acne (often improves in late pregnancy)
- Perioral dermatitis
- Telogen effluvium (hair shedding after the baby has been born)
- Striae gravidarum (stretch marks)
- Pyogenic granuloma
- Telangiectasia (dilated small blood vessels)
- Pigmentary disturbance (melasma).
Pregnancy makes management more difficult as many medications should be avoided.
Acne management in pregnancy can include the topical agents benzoyl peroxide and azelaic acid, and oral erythromycin for severe cases. Salicylic acid, topical retinoids, oral isotretinoin and tetracyclines should be avoided.
Prurigo of pregnancy
Itching is relatively prevalent in pregnancy. Causes include scabies, atopic eczema, contact irritant dermatitis etc. The itch is sometimes related to cholestasis (build up of bile) in pregnant women, and in others the cause is unknown.
Prurigo of pregnancy presents as scattered itchy/scratched papules (bumps) at any stage of pregnancy. Often no primary lesion can be found. It should be managed with emollients, and topical steroids may help individual papules.
Pruritic Urticated Papules and Plaques of Pregnancy
PUPPP is an acronym for Pruritic Urticated Papules and Plaques of Pregnancy, and is also known as polymorphous eruption of pregnancy. Features include:
- Onset of PUPPP is in the 3rd trimester and remission occurs within a few days of delivery
- It more frequently arises in primigravidae and multiple pregnancies
- Itchy erythematous papules and plaques first appear on abdominal striae and then spread to trunk and proximal limbs
- Direct immunofluorescence is negative (unlike pemphigoid gestationis)
- Emollients, medium potency topical steroids and sedative oral antihistamines provide relief of symptoms. In severe cases, systemic steroids may be necessary.
Pemphigoid gestationis is a rare blistering disease due to circulating IgG autoantibodies similar to those found in bullous pemphigoid, targeting a basement membrane zone protein BPAG2 (BP180) within the hemidesmosome. Features include:
- The onset of pemphigoid gestationis is most often in the 2nd trimester (weeks 13 to 26), but it may arise at any stage and may even be worse postpartum
- It can recur with menstruation, with oral contraceptives and in further pregnancies
- The itchy papules mainly affect the abdomen but may generalise, with grouped or annular red papules, plaques and blisters
- Direct immunofluorescence (a test done as part of a skin biopsy) shows deposition of C3 and or IgG or other antibodies
- Severe pemphigoid gestationis should be treated by oral corticosteroids.