The pelvic floor consists of layers of muscle that stretch like a hammock from the pubic bone in the front to the end of the backbone. These firm, supportive muscles are called the pelvic floor and they hold the bladder and bowel, as well as the internal genitalia/uterus in place. Certain conditions may cause the pelvic floor muscles to weaken. These are the same muscles you contract to stop peeing or squeeze during vaginal/internal intercourse. During pregnancy and birth, the pelvic floor muscles stretch and may become weakened. For some, this can cause urine to leak (urinary incontinence) for months to years after childbirth. A weakened pelvic floor can also allow the pelvic organs to drop from their usual position (internal genitalia/uterine prolapse). If the pelvic floor becomes weakened during pregnancy, pelvic floor exercises (i.e., kegel exercises) can strengthen your muscles and make it less likely that you will be incontinent or experience prolapse after birth. There is not a clear consensus however on how long and how often to do pelvic floor exercises.
For more information about the pelvic floor muscles including diagrams, videos, and step-by-step instructions on how to strengthen your pelvic floor muscles, please see the links below.