Department of Obstetrics and Gynecology, Akershus University Hospital, Lørenskog, and the University of Oslo, Faculty Division Akershus University Hospital, and the Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway.
Obstet Gynecol. 2013 Aug;122(2 Pt 1):329-336. doi: 10.1097/AOG.0b013e318299f62c.
To investigate whether pregnancy affects levator hiatus dimensions and the position and mobility of the bladder neck and the levator ani muscle in nulliparous pregnant women.
In the present study, 274 nulliparous pregnant women were examined at 21 weeks and 37 weeks of gestation using three-dimensional and four-dimensional transperineal ultrasonography at rest, during contraction, and during Valsalva maneuver. Levator hiatus dimensions were the anteroposterior diameter, the transverse diameter, and the area measured in rendered images. Positions of the bladder neck and levator plate were analyzed in the midsagittal plane, and mobility was calculated as displacement of the bladder neck or levator plate from rest to contraction or from rest to Valsalva.
A significant increase for all levator hiatus dimension measurements was found from 21 weeks to 37 weeks of gestation. The most marked change was found for levator hiatus area at rest and during Valsalva maneuver, in which the mean area was increased by 17.1% (11.7-13.7 cm(2)) and 21.4% (15.4-18.7 cm(2)), respectively. Bladder neck mobility changed significantly during pregnancy. The most marked change was seen from rest to contraction (mean -14 mm, standard deviation 0.4).
An increase of all hiatal dimensions as well as bladder neck mobility was found from 21 weeks to 37 weeks of gestation in nulliparous pregnant women. The findings indicate that the changes in pelvic organ support are not solely caused by delivery, but also by physiologic changes during pregnancy.
II.
探讨妊娠是否会影响未产妇的肛提肌裂孔尺寸以及膀胱颈和肛提肌的位置和活动度。
本研究采用三维和四维经会阴超声检查，于 21 周和 37 周妊娠时在静息、收缩和valsalva 动作时对 274 例未产妇进行检查。肛提肌裂孔尺寸为前后径、横径和在渲染图像中测量的面积。在正中矢状面分析膀胱颈和肛提板的位置，计算膀胱颈或肛提板从静息到收缩或从静息到valsalva 动作的移动度。
从 21 周到 37 周妊娠时，所有肛提肌裂孔尺寸测量值均显著增加。在静息和valsalva 动作时，肛提肌裂孔面积的变化最大，平均面积分别增加了 17.1%（11.7-13.7cm2）和 21.4%（15.4-18.7cm2）。妊娠期间膀胱颈活动度显著改变。最大的变化见于从静息到收缩（平均-14mm，标准差 0.4）。
未产妇从 21 周到 37 周妊娠时，所有裂孔尺寸以及膀胱颈活动度均增加。这些发现表明，盆腔器官支持的变化不仅是由分娩引起的，而且还与妊娠期间的生理变化有关。
Ⅱ级。
