Three Cases of Hyperpigmentation of Pregnancy

Some degree of hyperpigmentationdevelops in most pregnantwomen. This coloration is more pronouncedin dark-skinned women; onnaturally pigmented areas, such as theareolae, perineum, and umbilicus; andon the axillae, inner thighs, and otherregions that are prone to friction.The exact cause of physiologichyperpigmentation is not known.Melanocyte-stimulating hormonelevels are markedly elevated duringpregnancy. Estrogen and progesteronereportedly have melanocytestimulatingeffects. In pregnancy,hypertrophy of the intermediatelobe of the pituitary gland occurswith increased metabolism of proopiomelanocortinto μmelanotropin.Oral contraceptives may producesimilar cutaneous changes.Hyperpigmentation in a blackwoman. The abdomen of a 25-yearoldAfrican American woman in thethird trimester of pregnancy showedlinea nigra, intense linear hyperpigmentationfrom the symphysis pubisto the umbilicus (Figure 5). Lesspronounced hyperpigmentation wasnoted from the umbilicus to the xiphoidprocess; numerous striae alsowere seen.Dark pigmentation in a whitewoman.Increasing pigmentation ofthe umbilicus began in the firsttrimester of a 34-year-old woman'spregnancy. The area continued todarken until term (Figure 6). Thefine scar that bisects the patient'sumbilicus resulted from a previouslaparoscopy.Chloasma. The "mask of pregnancy,"or chloasma or melasmagravidarum, is seen on a 28-year-oldwoman who was 2 years postpartum(Figure 7). The patient was gravida5, para 3, aborta 2; her last child wasdelivered by cesarean section becauseof a breech presentation. Afterdelivery, the patient received 2 injectionsof medroxyprogesterone, 150 mg,3 months apart.The discoloration developed initiallyduring the fifth month of herpregnancy; it intensified throughoutthe remainder of gestation and hasremained unchanged since delivery.Exposure to sun temporarily heightensthe coloration. The patient hasnot taken oral contraceptives or hormonesother than the medroxyprogesteroneinjections since delivery.In most women, the hyperpigmentationregresses markedly or disappearscompletely after delivery. Ahydroquinone cream can be used tobleach or lighten the discoloration. (Cases and photographs courtesy of Dr Robert P. Blereau.)

References:

REFERENCES:

1.

Shornick JK, Meek TJ, Nesbitt LT Jr, Gilliam JN.Herpes gestationis in blacks.

Arch Dermatol.

1984;120:511-513.

2.

Winton GB, Lewis CW. Dermatoses in pregnancy.

J Am Acad Dermatol.

1982;6:977-998.

3.

Kolodny RC. Herpes gestationis. A new assessmentof incidence, diagnosis, and fetal prognosis.

Am J Obstet Gynecol.

1969;104:39-45.

4.

Holmes RC, Black MM. The fetal prognosis inpemphigoid gestationis (herpes gestationis).

Br JDermatol.

1984;110:67-72.

5.

Shornick JK. Herpes gestationis.

J Am Acad Dermatol.

1987;17:539-556.