Within the evaluation process for pelvic muscle health, a woman is often asked to "bear down" so that the examiner can assess muscle coordination. This maneuver is also utilized during assessment for prolapse or pelvic organ descent. Clinically, the patient's ability to perform a lengthening or bearing down is quite varied, depending upon many factors such as levator plate resting position, strength and coordination, childbearing status, and comfort with the maneuver. What are the implications of not being able to bear down? An interesting study published in 2007 concluded that women, when asked to perform a Valsalva maneuver (a forced expiration against a closed glottis), frequently co-contracted the levator ani muscles.
Participants included 50 nulliparous women between 36-38 weeks gestation and they were assessed with translabial 3D/4D ultrasound following emptying of the bladder. In almost half of the subjects, a pelvic floor muscle contraction was noted during the attempted Valsalva. Patients were provided with visual biofeedback to train the levator muscles to avoid a concurrent contraction, and despite the training, 11 of the 50 women were still unable to avoid a co-activation. (Keep in mind that for purposes of assessment, the prolapse would be best imaged or viewed if the levator muscles were not tightening.) For this reason, the study concludes that levator muscle co-activation is a significant confounder of pelvic organ descent. While a contraction of the pelvic floor muscles may be a positive, protective action when thoracic pressure is increased, a woman's degree of prolapse or pelvic organ descent may appear diminished during an examination. The authors of the study conclude that a clinician may have a false-negative finding for prolapse in the presence of strong, intact pubovisceral muscles.
This research highlights the value of being able to coordinate pelvic muscle activity with the trunk and with breathing. What is also very interesting is that the 50 women studied were all in late third trimester of pregnancy when assessed. Does the population studied have carry-over to non-pregnant women, or women who have never been pregnant? Does the co-contraction exist at the same rates for nulliparous, non-pregnant women? How will the lack of coordination for bearing down during increased trunk pressure affect labor and delivery? Is there a role for pelvic rehabilitation providers in assisting women who have difficulty coordinating the muscles of the trunk and pelvis prior to delivery? To the last question, I would answer "yes" when considering the women who have been referred to pelvic rehabilitation prior to labor and delivery. Having the opportunity to lengthen a tight, shortened pelvic floor, strengthen, alleviate pain in tissues from prior scars or from tension, and to improve confidence about the body's ability to perform the function of bearing down for childbirth can be a very positive preparation for a woman's childbirth experience.
For all the other research ideas that this article generates, we can see that many unanswered questions remain. Even when the research points us in valuable directions, having the skills to assess the patient to find out what is needed in her particular case is critical. For further refining of pelvic muscle assessment techniques, including skills for assessing and treating prolapse and pelvic organ descent, the Pelvic Floor Level 2B continuing education course offers lectures and labs. PF2B is next offered in early March in Oregon, and later this year in Illinois, North Carolina, and Missouri.