The anatomy of the pelvic floor
Let’s get the unsexy part out of the way: the anatomy lesson. The pelvic floor is a group of muscles that lines the pelvis, a bowl-shaped bone (made up of two halves) that joins with the sacrum, femur, and lower back. The nerves that control both sensation and muscle contraction come out of the low back and the sacrum, the triangle-shaped bone between the base of the spine and the tailbone. Three layers make up the pelvic floor muscles. The first layer of pelvic floor muscles forms a figure eight around the labia and the anal sphincter for vulva-havers, or around the base of the penis and anal sphincter for penis-havers. For everyone, there’s a triangle of support between the sit bones and the top of the pubic bone. The second layer is anatomically similar for all. We have an additional sphincter around the urethra and vagina-owners have another triangle of support parallel to the first layer. The third layer acts like a thick hammock that unites the two halves of the pelvis, providing stability for the trunk and support to the abdominal organs.The function of the pelvic floor
The pelvic floor muscles have five major functions:- Opening and closing the muscles around the urethra and anus to keep us continent, meaning we decide when to empty our bladder and bowels;
- Regulating the superficial sexual and reproductive muscles of the pelvic floor. For vagina-owners, the pelvic floor helps erect the clitoris during intimacy which can lead to stronger orgasms. For penis-owners, superficial pelvic floor muscles help to achieve and maintain the first third of an erection (the base of the penis);
- Supporting the organs of the lower abdomen like the bladder, the prostate, the uterus, and the rectum;
- Stabilizing your trunk any time your upper or lower body is moving, for example, when you walk, run, or jump;
- Shuttling blood and lymphatic fluid back towards the heart.