What Causes Skin Itching Before Period?

itchy skin before a period. i am 44 with no health problems,regular normal periods. i have been like this for approximatley 12mths and i had put it down to other allergies but i now think that it has something to do with my periods. i am 5ft 7 and weigh around 11stone. i never get ill and have never missed a period other than being pregnant. i have hayfever and kiwi fruit allergy.