[Multi-centric clinical study of trial of labor after cesarean section]

To study the feasibility and safety of trial of labor after cesarean section (TOLAC).

Retrospective analysis of five medical center of Guangdong province from January 2011 to December 2015 hospitalized delivery information, compare the same scar TOLAC (research group) with the scar pregnancy (control group) pregnancy outcomes, to study the feasibility and safety of TOLAC.

(1) During 2011-2015, total delivery 95 600 cases in five medical center, 13 824 cases of thme with uterine scar pregnancy, including 12 027 cases elective repeat cesarean section and 1 797 cases (13.00%, 1 797/13 824) with scar uterus vaginal trial of labor. Among 1 308 cases of vaginal delivery, the success for trial of labor rate was 72.79% (1 308/1 797). From 2011 to 2015, there were increased rate of pregnancy after cesarean section, which were respectively 10.71%, 13.28%, 14.45%, 15.54% and 16.98%. The will of vaginal birth were rising and the rate were respectively 11.85%, 12.25%, 13.49%, 13.82% and 12.93%. (2) There were 489 (27.21%, 489/1 797) cases of scar uterus maternal emergency cesarean section in the trial of labor, reason for "social factors" require for cesarean delivery have 68 cases, the percentage was 13.91% (68/489), compared with control group (7.18%, 206/2 869), the difference was statistically significant difference (χ(2)=27.356, P=0.000). Doctors diagnosed as "aura uterine rupture" in the labor was 11.86% (58/489), compared with that in control group (1.43%, 41/2 869), the differences were statistically significant difference (χ(2)=1 578.223, P=0.000). (3) The incidence of uterine rupture of the research group (0.74%, 9/1 211) was significantly higher than that of control group (0.01%,2/31 200; χ(2)> 2 000, P=0.000). The incidence of postpartum hemorrhage in research group was 6.94% (84/1 211), compared with that in the control group (3.05%, 951/31 200), there was statistically significant difference (χ(2)=16.328, P=0.000). While, there were no statistical significancefor the labor time limit, birth rate of severe asphyxia and neonatal birth weight average differences between two groups (P>0.05).

The rate of pregnancy after cesarean section is increasing year by year, and the will of vaginal birth is increasing, while it still are generally low. TOLAC is safe and feasible, but also significantly higher risk, strictly labor monitoring and can proceed fast cesarean delivery in delivery room is an important guarantee of safe delivery.