A diaper rash is a skin irritation under your baby’s diaper. The rash can be on the abdomen, genitals, and in the folds of the buttocks and thighs. Most babies develop a diaper rash at some time during infancy.

Thigh Folds on Baby
Baby
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A diaper rash develops when your baby’s skin is irritated. Irritation can be caused by:

  • Leaving dirty diapers on for too long
  • Too much moisture next to the skin
  • Diapers or plastic pants that are too tight
  • Allergic reaction to diaper material or detergent
  • Yeast or bacterial infection
  • Rubbing or chafing of the skin
  • Diarrhea