Stretch marks are caused when the skin expands too quickly causing a breakdown of collagen that produces what looks like a tear in the skin (stretch mark). These marks occur most commonly in the breasts, thighs and hips – especially after pregnancy or weight gain. The skin overlaying the stretch mark is very thin thus not a good candidate for laser, chemical peels and/or microdermabrasion because all these treatments are ablative (thin the epidermis). Collagen Induction Therapy keeps the epidermis intact while building the collagen in the dermal layers which makes the skin thicker and more even toned.