Jaki Nett's reply:
Weak pelvic floor muscles do not necessarily lead to a prolapsed uterus, but a prolapsed uterus will cause the pelvic floor muscles to become weak. A prolapsed uterus is caused by more than lax pelvic floor muscles--a prolapse occurs when there is a weakness to the cardinal and uterosacral ligaments complex. These ligaments help to maintain the upper vagina and cervix in position over the levator ani muscle (also known as the pelvic diaphragm or pelvic floor muscles), while maintaining the uterus in its inclined position.
There are two classifications of prolapsed uterus--incomplete and complete prolapsed. A complete prolapse occurs when the uterus, vagina, and bladder exit the body with the intestines following. Incomplete prolapse is the onset of the uterus starting its move downward. Once the sliding down of the uterus starts, lower abdominal hardness and pushing down or intra-abdominal pressure can exacerbate the prolapse.
Intra-abdominal pressure varies throughout the course of the day--for example, when we lift something heavy, the body automatically increases abdominal pressure to help stabilize the lumbar area (lower back). In addition, natural bodily functions are assisted with intra-abdominal pressure. But since intra-abdominal pressure is a major contributor to increasing the severity of a prolapse, close attention should be paid to how much is unconsciously used. To experience intra-abdominal pressure, pretend to cough and notice the lower abdominal area contracting and a downward pressure. Some people react to tension by chronically holding this pressure, which can lead to abdominal problems.
This pressure occurs in yoga postures too. For example, in Chaturanga Dandasana (Four-Limbed Staff Pose), intra-abdominal pressure assists to stabilize the torso to make the body rigid like a "staff."
To explore intra-abdominal pressure in a pose, lie back on the floor with the legs straight. Place one palm on the lower abdominals and one on the upper abdominals. Move into Urdhva Prasarita Padasana (Leg Lifts) by lifting the legs over the hips and bringing them perpendicular to the floor. Then ask yourself these questions: When lifting the legs, did the abdominals bellow out and become hard? Did the lumbar spine (lower back) arch up? This way of producing intra-abdominal pressure is injurious to the pelvic floor because pressure is being pushed in every direction except toward the head.
Bend the knees and place the feet on the floor. Soften the abdominal area and let all of the contents fall back toward the spine. Maintain this position and pull the whole abdominal area back toward the spine and make the waistline narrow, lift the chest and spread the diaphragm. This will look similar to the abdominal and diaphragm movements in Uddiyana Bandha, but the holding is softer.
Keeping the legs bent, slowly start to lift the feet off the floor. Notice how the pressure builds up. Bring the thighs perpendicular to the floor, then straighten the legs. Keep the spread of the diaphragm and the abdominal wall moving toward the spine. Make the waist long and narrow and then direct internal pressure upward. Here intra-abdominal pressure is still used to stabilize, but the downward pushing has been removed. If the abdominal area starts to bellow or the lower back arches when lifting or lowering the legs, bend the knees and put the feet back on the floor. Become familiar with intra-abdominal pressure and explore how it assists in poses.
For people who already have a prolapsed uterus, be cautious in standing poses because there is a chance that movement or jumping could aid in further slipping of the uterus. When all the supporting members in the pelvic cavity have lost tone, they do not have the resiliency to respond to the pull of gravity and weight. Inversions are the best poses to practice because gravity becomes an ally. While doing inversions, try to employ just enough intra-abdominal pressure to stabilize the lumbar spine but be conscious not to direct pressure that causes the pelvic floor to push toward the feet.
Salamba Sirsasana (Supported Headstand) held in proper alignment can help the organs move back into their proper placement. Niralamba Sarvangasana (Unsupported Shoulderstand) with toes supported on the wall may help the uterus to move back into position. With the support of the wall, this pose offers an opportunity to explore the internal pressure and to monitor and vary the movements of the pelvic floor.
Once the nature of intra-abdominal pressure is understood, the level of the prolapse might not change, but it will not be exacerbated.
Jaki Nett is a certified Iyengar Yoga instructor in St. Helena, California, and a faculty member of the Iyengar Yoga Institute of San Francisco. She teaches public classes in the San Francisco Bay Area and leads workshops in the United States and Europe, including specialty workshops on female issues.