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Bumps are a common skin condition during pregnancy, according to the American Academy of Dermatology, but this does not mean that they affect a lot of pregnant women. Approximately one in every 100 women develop a rash called PUPPP, or pruritic urticarial papules and plaques of pregnancy, according to the website BabyCenter. PUPPP involves small, itchy red bumps. Some pregnant women also experience prurigo of pregnancy, clusters of tiny bumps that might initially appear to be bug bites. Only one in 300 women will experience prurigo of pregnancy.


The causes of PUPPP and prurigo are unknown. The website Pregnancyetc suggests that PUPPP bumps are the result of inflammation caused by the stretching skin and tissue during pregnancy and that an increase in estrogen might also be a contributing factor.


PUPPP usually appears in first-time mothers and women carrying twins. The good news is that it probably won’t happen again in subsequent pregnancies, according to Pregnancyetc. Dr. Sophia Giatrakou of the University of Athens reports that male fetal DNA has been detected in the PUPPP bumps of some affected women, and that the condition might be linked to carrying male fetuses. PUPPP also seems to run in families.


PUPPP usually appears in your last trimester, according to BabyCenter, and it leaves as mysteriously as it starts, usually within weeks after you deliver. Prurigo starts a little earlier and lasts a little longer, up to three months after your baby is born. Pregnancyetc indicates that in rare cases, PUPPP might even start after delivery.


PUPPP usually starts on the abdomen and in stretch marks, then spreads to your legs and arms. Prurigo can begin anywhere, but most commonly it will appear on your hands and arms, legs and feet.


Depending on how severe your itching is, your physician might prescribe either a topical lotion, such as clobetasol or betamethasone, or an antihistamine such as Benadryl for PUPPP. In extreme cases, she might resort to oral steroids to give you some relief, according to BabyCenter. Only in rare cases is either condition harmful to you or your baby. PUPPP and prurigo are far more irritating than dangerous.


In rare cases, skin bumps and rashes can mimic PUPPP and prurigo, but be caused by cholestasis, a liver condition that causes bile to accumulate in the skin, according to Pregnancyetc. If you develop bumps, immediately bring them to your doctor’s attention so he can rule out cholestasis and give you some relief.