PUPPP rash during pregnancy

What is PUPPP?

PUPPP is a very itchy rash that affects pregnant women, usually in the third trimester.

PUPPP stands for pruritic urticarial papules and plaques of pregnancy. It's also called polymorphic eruption of pregnancy (PEP). It's had other names, too: nurse's late-onset prurigo, Bourne's toxemic rash of pregnancy, and toxic erythema of pregnancy.

Less than 1 percent of pregnant women (about 1 in 160 to 300) get a PUPPP rash, yet it's the most common pregnancy skin condition. It usually affects first-time moms and doesn't show up in later pregnancies.

What does PUPPP rash look like?

PUPPP rash first appears as small, raised spots that look like pimples. If you're light skinned, they may look pink or red, and you may be able to see a white halo around the eruptions. If you're darker skinned, the eruptions may appear closer to your skin color. PUPPP rash often shows up first on the stomach, in and around stretch marks (though you can get the rash even if you don't have stretch marks).

PUPPP can develop into larger patches of a hive-like rash. Blisters and large, raised areas may form. The rash may spread within a few days to the thighs, buttocks, back, and, more rarely, your arms and legs. It doesn't usually affect the neck, face, hands, or feet.

PUPPP rash can be intensely itchy, especially at night. It usually lasts for four to six weeks and disappears within a few days after delivery, though it can persist for a few weeks postpartum.

How is a PUPPP rash diagnosed?

A PUPPP rash is diagnosed by sight; your provider can tell by looking at the rash that it's PUPPP. If she wants to make sure there's not another infection causing the rash, she may order blood tests.

What causes PUPPP rash during pregnancy?

Experts don't know what causes a PUPPP rash. There are a couple of main theories about it, though:

• Rapid stretching of the skin may cause connective tissue damage, leaving the tissue vulnerable to inflammation. This would explain why PUPPP happens later in pregnancy (when skin stretches even more to accommodate your baby) and more often in women carrying multiples.
• PUPPP may be an allergy-like reaction to fetal cells in maternal blood. Male DNA circulating from the baby may deposit in the mom's skin, and the mom's immune system has a reaction to it. PUPPP appears twice as often in women carrying male babies.

Risk factors for PUPPP

Some women with the rash have no risk factors for PUPPP. But it's more common in women who:

• Are carrying multiples (The rate is 0.5 percent in singleton pregnancies, 2.9 to 16 percent in twin pregnancies, and 14 to 17 percent in triplet pregnancies.)
• Are having their first baby
• Are experiencing rapid or larger-than-usual weight gain in pregnancy
• Are Caucasian
• Are carrying a boy
• Have an in vitro fertilization (IVF) pregnancy with long progesterone treatment
• Have Rh positive blood type

Treatments for PUPPP rash

Treatments for PUPPP rash are intended to provide relief from the intense itching. Remedies to try include:

• A bath with oatmeal or baking soda
• Cool, wet compresses
• Aloe vera gel

Wearing soft, cotton clothing may help, too. Don't scratch the rash or it may worsen.

If the itching is still unbearable, your healthcare provider may recommend a topical ointment (corticosteroids), an oral antihistamine, or – if you have a severe case – she may prescribe oral steroids. Don't take any medications – even over-the-counter antihistamines or topical ointments – without talking to your provider.

Is PUPPP dangerous?

No, PUPP isn't dangerous for you or your baby. Though the itching may be difficult to live with – and it may be yet another thing keeping you from sleeping well – there are no other worrisome short-term or long-term consequences.

PUPPP isn't the only rash caused by pregnancy. Read about others in our article on rash during pregnancy.

Learn more:

• 6 pregnancy skin problems
• Itching during pregnancy
• Skin darkening during pregnancy (melasma or chloasma)
• Hair and nail changes during pregnancy