[Incidence of unintended pregnancy within 2 years after delivery and its influencing factors in China].

To investigate the present situation of unintended pregnancy within two years postpartum and its influencing factors in China. Participants who delivered a live birth at 60 hospitals in 15 provinces in the eastern, central and western regions of China during July 2015 to June 2016 were interviewed by using structured questionnaire. Information on occurrence of unintended pregnancy within 2 years after delivery, postpartum contraceptive use, sexual resumption, breastfeeding, and women's socio-demographic characteristics, and so on, were collected. Life-table analysis, cluster log-rank tests and a 2-level Cox regression model were used for data analysis. A total of 18 045 postpartum women were investigated. The cumulative 1- and 2-year unintended pregnancy rates after delivery were 5.3% (95%: 4.5%－6.1%) and 13.1% (95%: 11.3%－14.8%), respectively. Cox regression model analysis showed that the risk of unintended pregnancy within 2 years postpartum were increased in younger women, ethnic minorities, women with abortion history, and those who had a vaginal delivery with short lactation time and late postpartum contraceptive initiation (all <0.01). The risk of postpartum unintended pregnancy was not associated with geographic regions and hospitals where women gave a birth (all >0.05). In China, the risk of unintended pregnancy within 2 years after delivery is relatively high. Service institutions and service providers should improve the quality of postpartum family planning services, promote the use of high effect contraceptive methods, and educate women to use a method at the time of their sexual resumption or even before.