My sister had a pregnancy complication called ICP that caused her to have ichy skin all over, it's actually really serious and harmful to the baby. I would talk to your doctor or midwife and see if it's anything you should be concerned about or not.
Have you changed your diet lately? Or maybe your detergent? I'm not sure if itchiness is a pregnancy symptom, but I'd look to what your doing different. Strangely my husband is itchy all over also, no idea why. Lol
Try moisturizer. My skin gets itchy from the stretching