Skin problems in pregnancy
Introduction
Hormonal changes in pregnancy may result in physiological alterations in the skin, hair and nails. For example:
- Appearance or darkening of a vertical band down the middle of abdominal skin (linear nigra) which may normally appear paler than normal skin (linear alba)
- Darkening of areola, nipple and genital skin
- Increased redness of palms (palmar erythema)
- Telangiectasia (dilated small re blood vessels), venulectasia (dilated bigger blue-coloured vessels) and varicose veins
- Telogen effluvium (hair shedding after the baby has been born)
- Striae gravidarum (stretch marks)
- Skin tags on the neck, in the armpit and groin
Phyisological skin changes in pregnancy
Pregnancy may result in an increase in prevalence or severity of some common and uncommon skin problems. These include:
- Facial pigmentation (melasma)
- Atopic dermatitis (may worsen, improve or stay the same)
- Psoriasis (may worsen, improve or stay the same)
- Acne (often improves in late pregnancy)
- Perioral dermatitis
- Pyogenic granuloma
- Generalised pustular psoriasis
When prescribing for skin diseases, safety of medicines in pregnancy must be carefully considered.
Pregnancy eruptions
Itchy rashes during pregnancy
Itching is relatively prevalent in pregnancy. Causes include scabies, atopic eczema, contact irritant dermatitis etc. Some specific conditions that arise in pregnancy follow.
Cholestatic pruritus
Intrahepatic cholestasis affects about 1% of pregnancies. It results in unexplained pruritus (itch) during the second and third tremesters, with raised blood levels of bile acids and/or liver enzymes. Intrahepatic cholestasis is associated with:[1]
- Increased risk of preterm delivery
- Stillbirth (rare)
- Increased risk of later hepatobiliary cancer (2?? times greater than the risk in women in whom pregnancy occurred without intrahepatic cholestasis)
- Increased risk of later thyroid disease, diabetes, psoriasis, Crohn disease and cardiovascular disease
Prurigo of pregnancy
Prurigo of pregnancy (papular dermatitis of pregnancy) presents as scattered itchy/scratched papules at any stage of pregnancy. 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; umbilicus is spared
- 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
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, including umbilicus, 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.