By Joanne Stone, Keith Eddleman, Mary Duenwald

Pregnant women are subject to the same rashes that nonpregnant women get. One rash is unique to pregnancy, however: Pruritic Urticarial Papules of Pregnancy, or PUPP. It sounds scary, but it’s really more of a nuisance than anything else because it can cause some intense itching. It occurs more often during a first pregnancy and in women having twins or more (the more fetuses, the greater the likelihood).

PUPP tends to occur late in pregnancy and is characterized by hives or red patches that first appear in the stretch marks on your abdomen. These patches can spread to other areas on the abdomen and to the legs, arms, chest, and back. They almost never spread to the face. (Thank heaven for small favors.)

The good news is that the condition poses no risk to the baby. But if you develop this rash, your doctor may recommend that you have some blood tests to make sure you don’t have other conditions that can be associated with itching.

The only surefire way to make PUPP go away is to deliver. Some women tell us that the itching goes away within hours of giving birth. If delivery is still weeks away, it sometimes helps to bathe in a solution of colloidal oatmeal (Aveeno makes a good one). Skin lotions containing Benadryl can also help, but these products can sometimes dry the skin, which only makes the itching worse.

Some women get relief from taking Benadryl orally, but check with your doctor before doing so. Finally, in very severe cases (which are rare), the doctor may prescribe a short-term course of steroids or other medications.

Even if you don’t have a rash, you may notice that you itch a lot, especially where stretch marks develop. This itching is very common and usually is caused by the stretching of your skin as the baby gets bigger.

Up to 2 percent of pregnant women develop cholestasis of pregnancy, which is a condition where an increase of bile acids in the blood causes the itching. If the itching is mild, you can treat it with skin moisturizers, topical anti-itching medications, or oral antihistamines such as Benadryl (but remember to talk to your doctor first before taking).

If the itching is severe, your doctor may recommend oral medications that help to clear the bile acids from the bloodstream. Some studies have suggested that the baby should be monitored with non-stress tests when the mother has this condition, because it is associated with an increased risk of complications. The itching goes away shortly after delivery, but the condition may recur in future pregnancies.