I was scratching a lot too. I read this off baby center and it helped me. I used Curel lotion and Dove body wash. I'm in my second trimester and the itching has stopped.
Avoid hot showers and baths, which can dry out your skin and make the itching worse. Use mild soap and be sure to rinse it off well and towel off lightly. Then slather on an unscented moisturizer — some scents can cause irritation.
Try an occasional warm oatmeal bath. (You can buy oatmeal bath preparations in drugstores.) Wear loose cotton clothing and avoid going out in the heat of the day, since heat can intensify the itching.