No, but your legs do. Haha. Jokes aside, Only thing I can think of that does this is the body releases a
hormone called relaxin, which causes the joints in her pelvis to
literally relax. The body also releases the hormone progesterone during pregnancy, which
(among many things) loosens a woman’s ligaments and muscles. This
looseness helps the bones in the pelvis expand during labor, and thus
accommodate the baby’s head as it works its way down the birth canal.
