Skin Changes and Diseases in Pregnancy

Clinical Features of the Specific Dermatoses of Pregnancy

Atopic Eruption of Pregnancy (AEP)

• Key facts: accounts for 50% of all pregnancy-specific skin disorders. In 20% it is a flare of pre-existing atopic dermatitis; in 80% it appears for the first time.
• Timing: early onset, in the first or second trimester (before week 20).
• Appearance: dry red patches, eczematous papules and scratch marks concentrated in the skin folds (elbows, backs of the knees), or scattered itchy papules on the trunk and limbs. Serum IgE is raised in 20–70% of patients.

Polymorphic Eruption of Pregnancy (PEP / PUPPP)

• Key facts: the second most common benign inflammatory rash of pregnancy, typically seen in first pregnancies (nulliparous women) or multiple gestations.
• Timing: late onset in the third trimester (weeks 34–39) or immediately after delivery.
• Characteristic clinical picture:
  • Starts as intensely itchy red urticarial papules within the abdominal stretch marks (striae gravidarum).
  • Key feature: the skin around the navel is spared (periumbilical sparing), leaving a ring of about 1–2 cm of completely normal skin.
  • The rash gradually spreads to the thighs, buttocks and arms but never involves the face, palms or soles.

Pemphigoid Gestationis (PG / Herpes Gestationis)

• Autoimmune mechanism: IgG1 autoantibodies form against the BP180 antigen (collagen XVII, NC16A domain) in the epidermal basement membrane. The antibodies bind to the basement membrane and activate complement C3, leading to deposition and separation of the epidermis.
• Clinical features:
  • Onset in the second or third trimester (weeks 21–28).
  • Begins as red patches and urticarial papules right around the navel (periumbilical involvement), then quickly progresses to tense bullae filled with clear fluid that rupture, leaving painful, raw erosions.
• Histopathology and direct immunofluorescence (DIF): continuous linear C3 and IgG deposits along the basement membrane zone (BMZ).

Intrahepatic Cholestasis of Pregnancy (ICP)

• Key facts: the endocrine-metabolic disorder of pregnancy that poses the greatest danger to the baby.
• Mechanism: mutations in bile salt transporter genes (ABCB4/ABCB11), combined with high estrogen levels, reduce bile acid excretion and cause bile acids to build up throughout the body.
• Symptoms: intense itching of the palms and soles (worse at night) with no primary skin lesions at all (only secondary scratch marks).
• Warning sign: serum bile acids (SBA) above 10 µmol/L (especially above 40–100 µmol/L) raise the risk of acute fetal distress, preterm birth, meconium-stained amniotic fluid and stillbirth.

Safe Management of Skin Conditions in Pregnancy at Haute-Derma

At Haute-Derma, treatment during pregnancy follows the principle of fetal-maternal safety first, with every medication strictly assessed according to the FDA pregnancy safety categories:

Safe Skincare and Barrier Repair

• Purely physical (mineral) sunscreens: 15–20% zinc oxide and titanium dioxide protect across the full UV/HEV spectrum without being absorbed into the baby's circulation (oxybenzone and octinoxate are avoided entirely).
• Managing melasma and acne in pregnancy:
  • Azelaic acid 15–20% (FDA Category B): directly inhibits tyrosinase in overactive melanocytes, kills C. acnes and reduces inflammation, and is very safe for pregnant women.
  • Glycolic acid (< 10%): gentle superficial exfoliation that unclogs follicle openings.
  • Niacinamide 4–5%: blocks the transfer of melanosomes from melanocytes to keratinocytes and strengthens the ceramide barrier.
• Strictly contraindicated during pregnancy: retinoids (isotretinoin, tretinoin, adapalene – risk of birth defects), hydroquinone, spironolactone and high-strength salicylic acid (> 2%).

Medical Treatment in Collaboration With Obstetrics

• Managing AEP and PEP:
  • Short courses of class III/IV topical corticosteroids (hydrocortisone butyrate, triamcinolone acetonide) to settle the itch and redness.
  • Second-generation oral H1 antihistamines: cetirizine (10 mg/day) or loratadine (10 mg/day) (FDA Category B) to control nighttime itching.
• Urgent treatment of pemphigoid gestationis (PG): oral prednisolone (0.5–1.0 mg/kg/day) is started immediately, in coordination with the obstetrician, to stop the blisters from progressing.
• Urgent management of intrahepatic cholestasis (ICP):
  • Ursodeoxycholic acid (UDCA) 15 mg/kg/day to improve bile acid clearance, reduce toxicity and lower SBA levels.
  • Close fetal heart rate monitoring, with a planned multidisciplinary discussion about planned early delivery (usually by induction of labor) at weeks 36–37 to reduce the risk of stillbirth.

Safe Light-Based Therapy and Postpartum Recovery

• Narrowband UVB phototherapy (311 nm): shown to be safe for pregnant women with AEP, PG or treatment-resistant pregnancy itch; it suppresses T lymphocytes and relieves itching without affecting the baby.
• Postpartum skin restoration:
  • Red stretch marks (striae rubra): Vbeam Perfecta pulsed dye laser (595 nm) or long-pulsed Nd:YAG laser (1064 nm) targets hemoglobin to clear the dilated blood vessels within the stretch marks.
  • White stretch marks (striae alba): fractional radiofrequency (RF) microneedling combined with fractional CO2 laser creates deep micro-injuries in the dermis, stimulating new type I collagen and elastin to firm up lax skin.