Put your thumbs on your hip bones and reach your fingers backwards until they touch behind your spine (or as close as you can get). Now keep your thumbs on your hip bones and turn your fingers round to point in a forwards V at the front. That's the top of your pelvic bone. Inside your pelvis is your pelvic cavity, which holds your bladder, your womb and the end of your bowel. It's all held in place underneath by your pelvic floor, which holds it up against gravity.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/why-you-need-to-look-after-your-pelvic-floor