Value of computed tomography pelvimetry in patients with a previous cesarean section.

A case-control study was conducted at the Department of Obstetrics and Gynaecology, King Abdulaziz University Hospital, Jeddah, Saudi Arabia, to determine the value of computed tomography pelvimetry in patients with a previous cesarean section. Between January 1993 and December 1995, 219 pregnant women with one previous cesarean section met the criteria for vaginal birth after cesarean delivery. One hundred women had antenatal CT pelvimetry for assessment of the pelvis. One hundred and nineteen women did not have CT pelvimetry and served as control. Fifty-one women (51%) in the CT pelvimetry group delivered by cesarean section. Twenty-three women (23%) underwent elective cesarean section for contracted pelvis based upon the findings of CT pelvimetry and 28 women (28%) underwent emergency cesarean section after trial of labor. In the group who did not have CT pelvimetry, 26 women (21.8%) underwent emergency cesarean section. This was a statistically significant difference (P=0.02). There were no statistically significant differences in birthweight and Apgar scores in either group. There was no perinatal or maternal mortality in this study. Computed tomography pelvimetry increased the rate of cesarean delivery without any benefit in the immediate delivery outcomes. Therefore, the practice of documenting the adequacy of the pelvis by CT pelvimetry before vaginal birth after cesarean should be abandoned.