As with many of the annoying symptoms of pregnancy, itching breasts and nipples are probably caused by the pregnancy hormones in your body and your skin stretching as your breasts enlarge. Many women also feel this itching over their abdomen. The stretching dries your skin, so you might want to try a soothing lotion (one that does not have irritating perfumes in it), vitamin E ointment or cocoa butter, or an over-the-counter balm such as purified lanolin. Treatments to counter itching, such as calamine lotion or an Aveeno bath, may also help. I would not put calamine lotion directly on your nipples, however, as it may be drying. And try not to scratch, for that will only make the itching worse and your nipples tender. You don't want to cause dryness or tenderness of the nipples if you plan to breastfeed.