Nappy rash is most common in 9-12 month old babies, but all babies in nappies can develop it, so it's always best to be prepared! Nappy rash can be caused by:

• Your baby's skin being in contact with wee or poo (stools) for a long time.
• The nappy rubbing against your baby's skin.
• Not cleaning the nappy area or changing the nappy often enough.
• Using irritable or fragranced soaps, detergent or bubble bath.
• Using alcohol-based baby wipes.
• Your baby recently taking antibiotics.
  
  ^{* British Journal of Midwifery, September 2012, Vol 20, No 9}

• Your baby's nappy rash is spreading or getting worse.
• Your little one develops a persistent, bright red, moist rash with white or red pimples that spreads into the folds of their skin.