The pregnancy period is an important time characterized by various hormonal, vascular, metabolic, psychological, and immune system changes. During this period, in addition to naturally expected skin changes, various skin diseases specific to pregnancy that regress after delivery may also be observed.

Physiological (natural) skin changes are observed in the vast majority of pregnant women, disappear over time after delivery, and do not require treatment. The physiological skin changes observed during pregnancy can be summarized as follows:

  1. Chloasma (pregnancy mask): It is a discoloration that appears on the face, forehead-cheeks, upper lip area, and nose. Factors such as the last trimester of pregnancy coinciding with summer months and having darker skin increase the likelihood of chloasma. While it disappears after delivery in some women, it may be permanent in others. It usually increases with sunlight in summer and fades in winter. It is quite difficult to treat. Although depigmenting creams, glycolic acid, and peeling methods such as Jessner are used, the main factor is the continuous use of high-factor sunscreens throughout the year.
  2. Darkening of the skin: Darkening (usually brown-black) occurring in the nipples, external genital organs, and the midline of the abdomen gradually decreases and disappears after delivery.
  3. Increase in hair growth: Due to hormonal changes, increased hair growth may be observed in some areas and usually resolves after delivery.
  4. Others: Varicose veins (especially on the legs), increase in the number and size of moles, brittle nails, and increased sweating can be observed (1,2). Enlargement of pigmented moles may regress within 6–12 months after delivery. In cases of asymmetric growth or color change in moles, a dermatologist must be consulted, as the risk of malignant melanoma increases during pregnancy.

 

Stretch marks, called “striae distensae,” although considered physiological skin changes, may cause significant cosmetic concerns due to their permanence. To prevent their formation, the use of certain creams that increase skin production is recommended during pregnancy (after the first trimester). After pregnancy, treatments such as peeling, mesotherapy, and laser applied while the stretch marks are still red can reduce their visibility. If time has passed and the stretch marks have turned white, treatments will not be very effective.

Skin Diseases Specific to Pregnancy

They consist of a well-defined group of diseases that occur only during pregnancy and the early postpartum period.

Pregnancy-specific skin diseases can be examined under four main categories (1):

  1. Pemphigoid Gestationis
  2. Polymorphic Eruption of Pregnancy
  3. Intrahepatic Cholestasis of Pregnancy
  4. Atopic Eruption of Pregnancy

Pemphigoid Gestationis

It is an autoimmune (the immune system reacting against its own tissues) bullous (characterized by fluid-filled blisters) disease that usually occurs during pregnancy. Its incidence ranges between 1/1,700 and 1/50,000. It is more common in individuals with a genetic predisposition. It usually begins in the 2nd and 3rd trimesters (between the 4th and 9th months of pregnancy), but rarely it may appear in the first trimester or early postpartum period. Severe itching is the most important symptom. Itching starts around the navel and then spreads to the hips, trunk, arms, and legs. Lesions initially appear as red elevations and later develop into fluid-filled blisters (vesicles and bullae).

Although it regresses after delivery, exacerbations may occur postpartum in some patients. Therefore, follow-up after delivery is necessary. In some cases, the disease may recur before menstruation or with the use of oral contraceptives. There is a risk of premature birth and low birth weight. Rarely, temporary blisters may appear on the baby’s skin due to maternal antibodies (1,2,3,4).

The most important test for diagnosis is a small biopsy taken from the affected skin. When examined with special stains (direct immunofluorescence), a linear deposition along the basal membrane (junction between the epidermis and dermis) is diagnostic (complement 3) (2).

In treatment, anti-itch lotions and topical corticosteroids are used in early stages. However, if the disease becomes widespread, systemic corticosteroids are started and continued until the postpartum period. In resistant cases, treatments such as azathioprine, dapsone, immunoglobulin, and plasmapheresis may be used after delivery. An important point is that the disease may recur in subsequent pregnancies (2,3).

Polymorphic Eruption of Pregnancy

It is characterized by lesions concentrated in stretch marks, severe itching, and red, raised papules and plaques. It is a benign condition. It is commonly seen in the first pregnancy and in the 3rd trimester (last 3 months). Its incidence ranges between 1/130 and 1/300. Although the exact cause is unknown, it is thought that excessive stretching of the abdominal wall and resulting connective tissue damage trigger an immune response. Apart from causing discomfort due to itching, it has a good prognosis and does not harm the baby. It usually resolves within 6 weeks. The clinical appearance is typical and diagnostic; biopsy is rarely required (2,3).

Treatment usually includes topical corticosteroids, moisturizers, and antihistamines. In resistant cases, systemic corticosteroids may be needed (1,2).

Intrahepatic Cholestasis of Pregnancy

It is an itchy condition that occurs in the late stages of pregnancy due to cholestasis (cessation of bile flow). Due to severe itching, widespread scratch marks are more prominent compared to other pregnancy dermatoses. There is a risk for the fetus. If not treated early, fetal loss may occur. Its incidence ranges between 0.1–2.4%. Risk factors include gallstones, hepatitis C positivity, multiple pregnancies, and advanced maternal age. It is thought to result from increased bile acids in the serum. Treatment with “ursodeoxycholic acid” reduces risks for both mother and baby. Close monitoring is required. It may recur in subsequent pregnancies (3,4).

Atopic Eruption of Pregnancy

It is characterized by itching and eczema-like eruptions seen in pregnant women with atopy (genetic predisposition to allergies). Redness, itching, and small papules are observed on the face, neck, and inner parts of the arms. The skin is usually dry in these patients. It should be differentiated from other pregnancy dermatoses mentioned above. Serum IgE levels are elevated. There is no risk to the baby. It may recur in future pregnancies. Treatment includes medium-potency corticosteroids, moisturizers, and UVB phototherapy (2,3,4).

Besides these, other pregnancy-specific diseases are rare. The common features and importance of pregnancy dermatoses are as follows:

  1. They are usually very itchy,
  2. They occur mostly in the last trimester,
  3. In some cases, they may pose a risk to the baby,
  4. Treatment must be carefully planned considering benefit-risk balance due to limitations of medication use during pregnancy,
  5. Since they usually improve after delivery, in severe cases early delivery may be considered,
  6. Cooperation between obstetricians and dermatologists ensures proper patient education and treatment selection.

REFERENCES

  1. Ambros-Rudolph CM, Müllegger RR, Vaughan-Jones SA, et al. The specific dermatoses of pregnancy revisited and reclassified: results of a retrospective twocenter study on 505 pregnant patients. J Am Acad Dermatol 2006;54:395-404.
  2. Parlak AH. Pregnancy-specific dermatoses. Turkderm 2007; 41(1):1-7.
  3. Cohen LM, Kroumpouzos G: Pruritic dermatoses of pregnancy: to lump or to split? J Am Acad Dermatol 2007;56:708-709.
  4. Ambros-Rudolph CM: Dermatoses of pregnancy. JDDG 2006;9:748-759.

 

Assoc. Prof. Dr. İlgen Ertam,

Prof. Dr. Tuğrul Dereli.

Ege University Faculty of Medicine, Department of Dermatology and Venereology, İzmir.