Pregnancy can have a big impact on your skin. If you're lucky, you'll get that famous glow. But many women experience some unpleasant changes in their skin during pregnancy, including darkening often called the "mask of pregnancy" or a dark line stretching from the pubic area to the lower chest. Other changes include stretch marks, visible blood vessels, and reddened palms.

Darkening

According to David J. Leffell, MD, head of dermatologic surgery at Yale School of Medicine, 90% of pregnant women experience skin color darkening. In his book, Total Skin , Dr. Leffell says current theory suggests that hormonal changes stimulate skin darkening. This hyperpigmentation is usually in areas that are already heavily colored, including the nipples and areola, armpits, and genitals. Possible changes related to darkening include the following:

  • Mask of pregnancy —"Melasma" is the medical term for this condition. It usually affects the cheeks but can also darken the upper lip, chin, and forehead. Hormones and ultraviolet rays together cause the facial darkening. Debra Jaliman, MD, clinical instructor of dermatology at Mount Sinai School of Medicine, urges women to faithfully use a broad-spectrum sunscreen. "Since you can't change your hormone levels, you should protect yourself against ultraviolet light," she says. Many dermatologists suggest avoiding bleaching creams during pregnancy. If melasma lingers after delivery, visit your dermatologist.
  • Belly line —The official name for the dark line some pregnant women develop from their pubic area to their lower chest is "linea nigra." The good news is that it almost always disappears after delivery.

Acne

If you're prone to acne, says Dr. Jaliman, then "during the first three months, your skin may be the worst it's ever been." But after the third month, she says, the skin tends to clear.

Barbara R. Reed, MD, associate clinical professor of dermatology at the University of Colorado Health Sciences Center, believes over-the-counter acne creams and lotions are fine for pregnant women. Some prescription creams and lotions are also safe. But, she cautions, "Stay away from oral drugs if you can."

Discuss all prescription creams with your doctor before using them. Accutane, an oral drug for cases of severe cystic acne, should never be taken if pregnancy is a possibility, because it is known to cause serious birth defects.

Blood Vessel Growth

Blood circulation increases during pregnancy, and can cause the following changes in your skin:

  • Reddened palms —If your palms become pink or red, don't be alarmed. It's simply a visible sign of increased blood flow and will disappear after delivery.
  • Spider veins —These visible blood vessels are most common on the face, neck, and arms. Most disappear after delivery. If they persist after a few months after delivery, visit your dermatologist. He or she may treat your spiders with laser surgery. In the meantime, make-up may disguise the problem.
  • Varicose veins —You could develop enlarged veins on your legs during pregnancy and they may remain after delivery. Luckily, doctors have a variety of treatments to recommend following the birth of your child.
  • Bright red bumps —You may develop tiny red bumps called hemangiomas . These are balls of small blood vessels. Most vanish after delivery, but if they don't, your doctor can easily remove them.

Stretch Marks

Sorry. No matter what kind of cream or lotion you slather on, if you're going to get stretch marks, you'll get them. "There's no prevention," Dr. Jaliman explains, "because stretch marks are a break in the elastic tissue (of the skin)." She adds that no one can predict who will get these pinkish lines, which occur most often on the breasts, abdomen, buttocks, and hips.

Eventually, long after childbirth, stretch marks may fade and become less noticeable. If you haven't learned to live with yours after your baby has been weaned, talk to your dermatologist, who may treat them with laser therapy or with the prescription topical treatment Retin-A.

When to See Your Dermatologist

Moles may enlarge or darken during pregnancy and return to normal after delivery. But watch for signs of melanoma. Don't hesitate to have your doctor check suspicious growths. Dr. Leffell says that if any moles change significantly, a biopsy should be performed.

There are some rare yet serious skin conditions unique to pregnancy. See your doctor for any rash symptoms, including:

  • Blisters
  • Itchy red bumps
  • Severe general itching
  • Blemishes similar to acne on your buttocks, arms, or legs