Chapter 76: Skin Findings in Pregnancy

PATIENT STORY

A 32-year-old G3P2 woman presents with persistent itching in her 31st week of pregnancy. The itching is constant and worse at night. Her pregnancy had been uncomplicated, and she has no past history of medical problems. Many excoriations are noted and there are no blisters (Figure 76-1). She has no jaundice or scleral icterus. Her transaminases were greater than 300 and her total bilirubin was elevated at 2.1. Her bile salts were elevated and her hepatitis panel was negative. The ultrasound showed gallstones, but no obstruction was seen. A diagnosis of "intrahepatic cholestasis of pregnancy" was made, and the patient was treated with oral ursodiol (a bile salt binding agent) and topical 1% hydrocortisone cream. The bile salts and transaminases were decreased and the patient's pruritus improved but did not resolve until after delivery.¹

INTRODUCTION

Maternal skin and skin structures undergo numerous changes during pregnancy. There are two general categories of pregnancy-associated skin conditions: (a) benign skin conditions associated with normal hormonal changes of pregnancy (striae gravidarum, hyperpigmentation, hair and vascular changes), and (b) pregnancy-specific dermatoses (prurigo of pregnancy, intrahepatic cholestasis of pregnancy, pustular psoriasis of pregnancy).

SYNONYMS

• Striae gravidarum—Stretch marks.

• Atopic eruption of pregnancy, eczema in pregnancy, prurigo of pregnancy, and pruritic folliculitis of pregnancy.

• Spider telangiectasias—Spider nevi or spider angiomas.

• Intrahepatic cholestasis of pregnancy—Pruritus gravidarum.

EPIDEMIOLOGY

• Almost all pregnant women develop some increase in skin pigmentation. This usually occurs in discrete areas, probably because of differences in melanocyte density.

• Striae gravidarum (stretch marks) occur in up to 90% of pregnant women by the third trimester.²

• Spider telangiectasias occur in approximately 66% of light-complected and 10% of dark-complected pregnant women, primarily appearing on the face, neck, and arms. The condition is most common during the first and second trimesters.³ Palmar erythema occurs in approximately two-thirds of light-complected and up to one-third of dark-complected pregnant women.²

• Hemorrhoidal, saphenous, and vulvar varicosities occur in approximately 40% of pregnant women.³

• Prurigo of pregnancy (now called atopic eruption of pregnancy) occurs with an incidence of approximately 1 in 300 to 1 in 450 pregnancies.^4,5

• Intrahepatic cholestasis of pregnancy occurs in approximately 1 of 146 to 1293 pregnancies in the United States.³

ETIOLOGY AND PATHOPHYSIOLOGY

• The most common skin pigmentary change is darkening of the linea alba (Figure 76-2), which is then called the linea nigra.⁶ It may span from the pubic symphysis to the umbilicus or all the way to the xiphoid process.

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