It is estimated that well over half of pregnant women develop pelvic or back pain. Of all women with chronic low back pain, one quarter of those developed the problem during pregnancy. That’s a lot of people, and a lot of pain.
What can be done? As with many conditions, there are only theories. In this case, the pain is thought to be caused by a wobbly pelvis. During pregnancy, the pelvic joints and muscles become loose because women’s bodies produce joint-relaxing hormones. The pressure of the pregnancy in the pelvis also causing stretching. Would strengthening the muscles that support the pelvis and back help reduce the problems? Or would exercising put more force on the already pressured joints and muscles? This study found that unsupervised exercise did not help any more than instructions to avoid exercise. And some of the exercises actually made symptoms worse.
These researchers assigned 44 women with post-delivery pelvic pain to one of three groups. One group was assigned to do exercises for the muscles that connect diagonally on the front and back of the trunk. The second group worked the muscles running up and down from the ribs and spine to the pelvis bone. The third group didn’t do any exercise; they were instructed to do their usual day-to-day activities. Participants had completed their pregnancy an average of just over four months before taking part in the study.
Each woman was sent a video tape describing pelvic pain, how to move and lift safely, what to do when pain strikes, and how to use a pelvic belt (an elastic band that wraps around the waist to hold the pelvis steady). Each person got the same information, but members of the two exercise groups also watched sections on how to do their exercise routine, which they followed for eight weeks.
Many of the women who worked their diagonal muscles found that training made the pain or fatigue worse. One-fourth had to stop the training because they felt too much pain. The routine for this group included an exercise for the large hip extensor muscles, requiring them to lift their leg up while lying face down. The authors think this exercise may have put too much pressure on the pelvis, leading to the increase in pain.
Although most of the participants showed improvement over the eight weeks of the study, there weren’t any remarkable differences between either exercise routine. In fact all three groups, even those who didn’t do any exercise, improved at about the same rate.
Looking back, the researchers wondered if the way the training was done could have affected the outcome in the exercise groups. They consider that having one-on-one coaching might make a difference. At this point, however, exercising the diagonal trunk muscles does not appear to offer an advantage over instructions only.
The authors emphasize the need for additional research to see if pelvic pain can be eased by avoiding hip extensor exercises, and whether there are other types of abdominal exercises that would be more helpful for patients with pelvic pain after pregnancy.