Effects of two-child policy on cesarean section rate in China: analysis under Robson Ten-Group Classification

Objective To investigate the changes in cesarean section rate(CSR) after the announcement of universal two-child policy using the Robson Ten-Group Classification. Methods A retrospective study was conducted to analyze 9 734 deliveries in the First Affiliated Hospital of Soochow University from January 2013 to August 2016. All deliveries were classified by the Robson Ten-Group Classification System and divided into three subgroups including phase 1(delivered between January 2013 and November 2013, the period before the selective two-child policy was implemented), phase 3( delivered between October 2015 and August 2016, the period after the universal two-child policy was implemented) and phase 2 (delivered between December 2013 and September 2015, the transition period from selective two-child policy to the universal two-child policy). Changes in CSR were analyzed by Chi-square test and Logistic regression. Results The cesarean section deliveries in Group 2b (singleton, cephalic presentation, primipara, ≥37 gestational weeks, cesarean section before labor) and group 5 (singleton, cephalic presentation, multipara with at least one cesarean section history, ≥37 gestational weeks) accounted for 52.78% (2 062/3 907) of the total cesarean section deliveries. The overall CSR decreased in phase 3 than in phase 1 [34.29% (654/1 907) vs 43.71% (1 112/2 544), χ2=40.376, P=0.000], and the most remarkable decline was found in group 2b [5.35% (102/1 907) vs 14.27% (363/2 544), χ2=92.700, P=0.000]. Compared with phase 1, in all deliveries, the constituent ratio of deliveries of groups 1 and 2 (singleton, cephalic presentation, primipara, ≥37 gestational weeks) was decreased in phase 3 [50.24% (958/1 907) vs 60.34% (1 535/2 544), χ2=45.145, P=0.000], while that in groups 3 and 4 (singleton, cephalic presentation, multipara, ≥37 gestational weeks, no cesarean section history) [21.66% (413/1 907) vs 16.71% (425/2 544), χ2=17.483, P=0.000] as well as in group 5 [14.47% (276/1 907) vs 9.28% (236/2 544), χ2=28.910, P=0.000] were increased. In group 5, the rate of vaginal birth after cesarean in phase 3 was higher than that in phase 1 [17.39% (48/276) vs 2.54% (6/236), χ2=29.732, P=0.000]. Conclusions The proportion of multiparae significantly increases, while the overall CSR significantly decreases after the implementation of universal two-child policy in China. Gravidas in groups 2b (singleton, cephalic presentation, primipara, ≥37 gestational weeks, cesarean section before labor) and 5 (singelon, cephalic presentation, multipara with at least one cesarean section history, ≥37 gestational weeks) are the most important target population in attempting to reduce CSR in China.