NEUROUROLOGY & FEMALE UROLOGY

Displacement and Recovery of the Vesical Neck Position during Pregnancy and After Childbirth
Wijma J, Weis Potters AE, van der Mark TW, Tinga DJ, Aarnoudse JG
Martini Hospital Groningen, Groningen, The Netherlands
Neurourol Urodyn. 2007; 26: 372-6

• Aims: (i) To describe the displacement and recovery of the vesical neck position during pregnancy and after childbirth and (ii) to discriminate between compliance of the vesical neck supporting structures with and without pelvic floor contraction.
• Methods: We focussed on the biomechanical properties of the vesical neck supporting structures during pregnancy and after childbirth by calculating the compliance and the hysteresis as a result from of abdominal pressure measurements and simultaneous perineal ultrasound.
• Results: This study shows that compliance of the supporting structures remains relatively constant during pregnancy and returns to normal values 6 months after childbirth. Hysteresis, however, showed an increase after childbirth, persisting at least until 6 months post partum.
• Conclusions: Vaginal delivery may stretch and or load beyond the physiological properties of the pelvic floor tissue and in this way may lead to irreversible changes in tissue properties which play an important role in the urethral support continence mechanism.
  
  
• Editorial Comment
  This manuscript reviews the effects of vaginal delivery on the biomechanical properties of the bladder neck and the pelvic tissues that support same. The authors found that the dynamic properties of the pelvic floor tissue only undergo a transient change and by six months, the dynamic component has returned to normal. In contrast, the effects of childbirth on hysteresis (failure of tissue to follow the same course during relaxation as during distention) are permanently altered with pregnancy. It is stated in the manuscript that the changes are potentially secondary to the delivery overwhelming the intrinsic properties of the pelvic floor tissues thus leading to permanent alteration. Along these same lines, the effectiveness of cesarean section in preventing the development of post-partum stress urinary incontinence has already been reported in the literature and reviewed in this journal (1).

Reference

1. Groutz A, Rimon E, Peled S, Gold R, Pauzner D, Lessing JB, et al.: Cesarean section: does it really prevent the development of postpartum stress urinary incontinence? A prospective study of 363 women one year after their first delivery. Neurourol Urodyn. 2004; 23: 2-6.

Dr. Steven P. Petrou
Associate Professor of Urology
Chief of Surgery, St. Luke’s Hospital
Associate Dean, Mayo School of Graduate Medical Education
Jacksonville, Florida, USA
E-mail: petrou.steven@mayo.edu