Rashes and Itching in Pregnancy - Part 1

During pregnancy, the body undergoes a multitude of changes and skin is no exception to this rule. With so much change, it might be easy to overlook the start of a new rash or a few itchy bumps. However, these may indicate the start of a skin condition that can affect pregnancy in more ways than one. In this article, we provide a brief overview of pregnancy-related dermatoses.

We will focus on the signs and symptoms of each diagnosis as well as the recommended treatment strategy. Since we would like to go into some detail about each of these conditions, we will focus on two of these conditions, polymorphic eruption of pregnancy and papular dermatoses of pregnancy in part 1 of this two-article series:

• Polymorphic eruption of pregnancy – Part 1
• Papular dermatoses of pregnancy – Part 1
• Pemphigoid gestationis – Part 2
• Intrahepatic cholestasis of pregnancy – Part 2
• Impetigo herpetiformis – Part 2

Polymorphic Eruption of Pregnancy, PEP (Pruritic Urticarial Papules and Plaques of Pregnancy, PUPPP)

The onset of this condition is sudden and usually occurs in the last trimester of pregnancy, but there have been some reports of this occurring even after delivery. As the name suggests, this rash begins as very itchy hive-like bumps which erupt on the abdomen, usually in and around stretch marks. They also commonly appear on the upper thighs. However, the rash can appear almost anywhere on the body. These bumps often come together to become bigger, redder plaques. Later on, the rash can transform/evolve to include vesicles (fluid-filled bumps).^[1] As this skin condition is called “polymorphic,” which means having a variety of physical appearances, these lesions can also sometimes appear as solid bumps interspersed with fluid-filled bumps, be targetoid, or resemble the weepy red crusted lesions of eczema.^[2]

Although this condition can be extraordinarily itchy and uncomfortable for mom, it is generally not a cause for concern. It is one of the most common skin conditions to occur during pregnancy, affecting 1 out every 160 pregnancies. Most affected individuals have a clearing of their skin within 4-6 weeks (a few days postpartum) with no residual scarring or pigment changes. The development of the baby is not affected by this condition, and the majority of mothers go on to deliver a healthy infant, given there are no other conditions affecting a baby’s growth.^[1]

Most patients decide to treat their condition, despite no long-term effects, due to the intense itching experienced with PEP. The most common treatments include over the counter soothing, anti-itch creams, and lotions. Mild topical steroids such as fluticasone are sometimes recommended as first-line therapy. The topical steroid can help with itch as well as the appearance of the lesions. First-generation antihistamines such as diphenhydramine (the main ingredient of Benadryl) have also been used with some success. However, these medications are sedating and can make the patient very sleepy.^[2] For most people, the treatments described above usually provide a significant degree of relief.

Papular Dermatoses of Pregnancy

There is some controversy that surrounds the classification of the following conditions, but we will discuss three types of skin rashes that fall under the title “papular dermatoses of pregnancy.” These include prurigo of pregnancy, pruritic folliculitis of pregnancy, and eczema of pregnancy.

Prurigo of pregnancy (PP)

This is another common, extremely itchy rash consisting of red bumps (usually <0.5 cm in size) that appear most commonly on the arms, legs, hands, and feet. It usually appears around 25-30 weeks of pregnancy. Scarring and changes in rash appearance occur more often than not due to itching and picking at lesions.^[3]

Again, this rash does not result in any serious side effects for the mother or the baby. Treatment usually consists of moderate to strong topical steroid medications, antihistamines such as diphenhydramine or chlorpheniramine, or short courses oral steroids if necessary.^[3]

Pruritic folliculitis of pregnancy (PFP)

Unlike prurigo of pregnancy, and opposite to what its name suggests, this condition is usually not itchy although it can be. The rash consists of red bumps associated with hair follicles that can be either sterile or filled with pus. The rash generally starts on the belly then spreads to the chest, back, arms, and thighs. Most women notice the rash in their second or third trimester of pregnancy.^[3,4]

Although the rash can be of cosmetic concern for the affected patient, it does not have any long-term effects on the health of the mother or baby. For mom, the rash usually goes away after 1 month of delivery.

Treatment consists of topical low-strength steroids and benzoyl peroxide. Ultraviolet B radiation therapy has also been tried with some success. Of course, since these lesions are often asymptomatic, no treatment is necessary if that is the preference of the patient.

Eczema of pregnancy (EP)

This is the most common condition seen in pregnancy and is characterized by lesions seen in individuals with eczema. It is usually seen before the third trimester in most patients. Some patients who experience this condition already have a diagnosis of eczema (20%) whereas around 80% of patients experience an eruption for the first time. There are two types of EP which include the E-type and the P-type. The E-type is the more common type and consists of the patchy, itchy lesions seen in eczema and appears in typical locations such as the neck, face, and the creases of the elbows and knees. The P-type consists of small, itchy red bumps that can appear anywhere on the body.^[1,5]

Although this condition can persist throughout a woman’s pregnancy, it does not result in any adverse effects on the baby or mother.^[1]

Treatment consists of what is used to manage eczema in non-pregnancy patients, including topical steroids, antihistamines, and over-the-counter emollients.^[1]

See part 2 of the rash and itching in pregnancy series.