Is there a synergistic relationship between diaphragm and pelvic floor muscles in pregnant women?

The aim of this study is to examine whether there is a synergistic relationship between the diaphragm and pelvic floor muscles (PFM) in pregnant women.

Our study was carried out as a cross-sectional study in primigravid pregnants in the second and third trimesters. Superficial electromyography (EMG), 2D/3D ultrasonography (USG), pulmonary function test (PFT), PERFECT, maximum expiratory pressure (MEP) and inspiratory pressure (MIP) measurements were used to evaluate pelvic floor and diaphragm muscle functions during pregnancy. Mann-Whitney U test was used to show the change in the second and third trimesters, and Spearman correlation was used to determine the relationship.

No correlation was found between the EMG data of the PFM and diaphragm, or between the USG data of the PFM and diaphragm in all participants, in the second and third trimesters. In the third trimester of the study, diaphragmatic thickness and levator hiatal area (LHA) decreased and both diaphragm and PFM % MVC EMG parameters increased. In the third trimester, FVC, MIP, MEP decreased, and nonsignificant increase in FEV1, FEV1/FVC and peak ekspiratuar flow(PEF) were detected. A significant correlation was found between pelvic floor levator hiatal area USG and FEV1/FVC in both trimesters (r: 0,577p: 0,004).

There may be a synergistic relationship between the diaphragm and PFM in pregnant women, the relationship may weaken as pregnancy progresses, and there may be no coactivation relationship between the two muscles. In order to prevent the occurrence of pelvic floor dysfunction during pregnancy and to increase the effect of rehabilitation programs, the relationship between the diaphragm and the PFM should be determined and more studies should be conducted.