Stretch marks on my back and skin getting scratchy for no reason. why?

What's your age?: Stretch marks can show up on the back during puberty or adolescence, pregnancy, or taking male hormones. They could also show up it there's been weight gain. Itchy skin could be related to dryness. If these conditions don't apply, there's a possibility of a hormone imbalance, like a thyroid or adrenal gland mnalfunction. Those would have to be ruled out by blood tests and physical exam.