my wife is in the end of her ninth month and a few days ago she noticed a strait horizontal line or fold on the bottom of her stomach. similar to the line underwear makes on skin, except that its not in the right place for it to be that. under the line her skin is sometomes softer and puffier, so the line is kind of a seperation between the rest of her abdomen. is this normal? she is feeling reglar movements of the baby