If it occurs before your period then it is normal. One thing I noticed that was happening to me was the deodorant in my pantyliners was contributing to the itching. So, I use only unscented now. The itching isn't as severe. Also, right before a woman begins her period, she gets a white to yellowish discharge, which is also normal. This can also itch some. If there is a smell associated with the discharge, then you do have a yeast infection.