Is it permissible to remove stretch marks resulting from pregnancy that cause embarrassment to the the wife?

There is no harm in cosmetic surgical procedures to remove a defect, pain, or a disfiguring blemish that severely mars one's appearance, unlike those done purely for beauty and to enhance one's looks, which are impermissible. The stretch marks on the abdomen due to pregnancy and childbirth do not reach the level of disfigurement, and therefore, it is not permissible to undergo cosmetic surgery to remove them.