Labor induction to stop itchiness?

It sounds like you're having some kind of allergic reaction to something. When you had your liver test, did they do an ultrasound? You may have a skin allergy to the lube they used on you. Stretch marks are bad enough but if you scratch you could cause worse irritation. If this isn't better tomorrow I say go to the emergency room and insist on being seen. Whether they decide to induce you or not, leave that up to them, but it sounds pretty bad and you don't want to be worrying about an itchy belly when your baby arrives.