A retrospective cohort survey of problems related to second childbirths during the 2-child policy period in Jiangbei District of Ningbo City in China.

From 1979 to 2014 in China, a 1-child policy was imposed to control population growth. During 2014 to 2015, families in which 1 spouse was only 1 child were eligible to apply for planning a second child. To foresee issues affecting obstetrical departments related to the introduction of the universal 2-child policy in 2016, we retrospectively investigated the demographics and health-related outcomes of second pregnancies in families applying for a second child in Jiangbei District of Ningbo City during January 17, 2014, to January 14, 2016.A retrospective cohort survey was conducted for Jiangbei District of Ningbo City from January 17, 2014, to January 14, 2016, with reference to data from 2012 to 2014.Applications for a second birth increased after implementation of the 2-child policy, from 505 in 2012 to 2013, to 1222 in 2014 to 2015. Until the end of this study (December 31, 2016), 739 women gave birth to a second child, among whom 21.38% were aged ≥35 years. Rates of cesarean deliveries (59.68%) and gestational diabetes mellitus (14.21% of women) were each positively associated with the age of the mother. Among women aged ≥35 years, 37.97% refused prenatal screening.Introduction of the 1-child policy encouraged more families to apply for a second child, with many women aged ≥35 years, leading to higher rates of cesarean deliveries and adverse complications. A high percentage of eligible older women refused prenatal screening. Obstetric departments should adjust perinatal health management schemes to prepare for similar probable changes associated with the universal 2-child policy.