Anke Reitter1, Betty-Anne Daviss2, Andrew Bisits3, Astrid Schollenberger4, Thomas Vogl4, Eva Herrmann5, Frank Louwen6, Stephan Zangos4. 1. Department of Obstetrics and Gynecology, Goethe University, Frankfurt, Germany. Electronic address: ankereitter@googlemail.com. 2. Midwifery Division, Department of Obstetrics and Gynecology, Montfort Hospital, Ottawa, ON, Canada. 3. Royal Hospital for Women, University of New South Wales, Randwick, NSW, Australia. 4. Department of Radiology, Goethe University, Frankfurt, Germany. 5. Department of Biostatistic and Mathematic Modeling, Goethe University, Frankfurt, Germany. 6. Department of Obstetrics and Gynecology, Goethe University, Frankfurt, Germany.
Abstract
OBJECTIVE: The purpose of this study was to assess the impact of different positions on pelvic diameters by comparing pregnant and nonpregnant women who assumed a dorsal supine and kneeling squat position. STUDY DESIGN: In this cohort study from a tertiary referral center in Germany, we enrolled 50 pregnant women and 50 nonpregnant women. Pelvic measurements were obtained with obstetric magnetic resonance imaging pelvimetry with the use of a 1.5-T scanner. We compared measurements of the depth (anteroposterior (AP) and width (transverse diameters) of the pelvis between the 2 positions. RESULTS: The most striking finding was a significant 0.9-1.9 cm increase (7-15%) in the average transverse diameters in the kneeling squat position in both pregnant and nonpregnant groups. The average bispinous diameter in the pregnant group increased from 12.6 cm ± 0.65 cm in the supine dorsal to 14.5 cm ± 0.64 cm (P < .0001) in the kneeling squat; in the nonpregnant group the increase was from 12 cm ± 0.76 cm to 13.9 cm ± 1.04 cm (P < .0001). The average bituberous diameter in the pregnant group increased from 13.6 cm ± 0.93 cm in the supine dorsal to 14.5 cm ± 0.83 cm (P < .0001) in the kneeling squat position; in the nonpregnant women the increase was from 12.6 cm ± 0.92 cm to 13.5 cm ± 0.88 cm (P < .0001). CONCLUSION: A kneeling squat position significantly increases the bony transverse and anteroposterior dimension in the mid pelvic plane and the pelvic outlet. Because this indicates that pelvic diameters change when women change positions, the potential for facilitation of delivery of the fetal head suggests further research that will compare maternal delivery positions is warranted.
OBJECTIVE: The purpose of this study was to assess the impact of different positions on pelvic diameters by comparing pregnant and nonpregnant women who assumed a dorsal supine and kneeling squat position. STUDY DESIGN: In this cohort study from a tertiary referral center in Germany, we enrolled 50 pregnant women and 50 nonpregnant women. Pelvic measurements were obtained with obstetric magnetic resonance imaging pelvimetry with the use of a 1.5-T scanner. We compared measurements of the depth (anteroposterior (AP) and width (transverse diameters) of the pelvis between the 2 positions. RESULTS: The most striking finding was a significant 0.9-1.9 cm increase (7-15%) in the average transverse diameters in the kneeling squat position in both pregnant and nonpregnant groups. The average bispinous diameter in the pregnant group increased from 12.6 cm ± 0.65 cm in the supine dorsal to 14.5 cm ± 0.64 cm (P < .0001) in the kneeling squat; in the nonpregnant group the increase was from 12 cm ± 0.76 cm to 13.9 cm ± 1.04 cm (P < .0001). The average bituberous diameter in the pregnant group increased from 13.6 cm ± 0.93 cm in the supine dorsal to 14.5 cm ± 0.83 cm (P < .0001) in the kneeling squat position; in the nonpregnant women the increase was from 12.6 cm ± 0.92 cm to 13.5 cm ± 0.88 cm (P < .0001). CONCLUSION: A kneeling squat position significantly increases the bony transverse and anteroposterior dimension in the mid pelvic plane and the pelvic outlet. Because this indicates that pelvic diameters change when women change positions, the potential for facilitation of delivery of the fetal head suggests further research that will compare maternal delivery positions is warranted.
Authors: Alik Huseynov; Christoph P E Zollikofer; Walter Coudyzer; Dominic Gascho; Christian Kellenberger; Ricarda Hinzpeter; Marcia S Ponce de León Journal: Proc Natl Acad Sci U S A Date: 2016-04-25 Impact factor: 11.205
Authors: Janine Hoffmann; Katrin Thomassen; Patrick Stumpp; Matthias Grothoff; Christoph Engel; Thomas Kahn; Holger Stepan Journal: PLoS One Date: 2016-08-17 Impact factor: 3.240