This study utilizes four waves of data from 1997-2017 China Fertility Survey and analyzes the levels and trends of induced abortion since the early 21st century. Married women of reproductive age who had pregnancy history within the five years before each survey were selected as research object. The study dissected the characteristics of induced abortion in different periods, including the number and gender of children, contraceptive use, and other relevant information. The results show that the occurrence of induced abortion decreased gradually, and the risk of induced abortion was higher for those who had given birth to less children. Meanwhile, induced abortion among 2-children women increased recently. It is noteworthy that premarital induced abortions among childless women continued to increase in recent years, and the sexual and reproductive health issues of adolescents remained serious. The occurrence of induced abortions after childbirth increased for those with one or two children, showing that the unmet need for contraception after childbirth should gain more attention. In addition, sex-selective abortion has been decreasing gradually but still exists. Therefore, gender equality advocacy needs to be strengthened.

Fertility intention,fertility behavior and the use of contraceptive measures have changed greatly since the early 21st century.This paper analyzes the contraceptive rate,contraceptive mix of married women at childbearing age using the data from 2010 to 2016,and discusses the changes in contraceptive patterns in the new era and the relationship between contraceptive use and induced abortion.The analysis shows that in the new period,especially after the adjustment and improvement of fertility policy,the composition of contraceptive mix has changed significantly:the IUD use has declined slightly,sterilization showed a dramatic decrease and the use of condom increased remarkably.In particular,the proportion of condom use has significantly changed since the late 2015 when the universal two-child policy was implemented.The contraceptive mix of different regions in China has its own characteristics,which is closely related to the different provisions and implementation of family planning.With the reduction of long term contraceptive methods and the increase of short acting methods,the risk of induced abortion increased significantly.

Ｂａｓｅｄ ｏｎ ｔｈｅ Ｄｅ Ｊｕｒｅ Ｐｏｐｕｌａｔｉｏｎ Ｄａｔａｂａｓｅ ｏｆ ｔｈｅ １２１ Ｎａｔｉｏｎａｌ Ｍｏｎｉｔｏｒｉｎｇ Ｃｏｕｎｔｉｅｓ ｉｎ ２０１３ ｆｒｏｍ ｔｈｅ Ｎａｔｉｏｎａｌ Ｈｅａｌｔｈ ａｎｄ Ｆａｍｉｌｙ Ｐｌａｎｎｉｎｇ Ｃｏｍｍｉｓｓｉｏｎ，ｔｈｉｓ ｓｔｕｄｙ ｅｍｐｌｏｙｓ ｔｈｅ ｒｅｖｉｓｅｄ Ｌｅｅ?Ｃａｒｔｅｒ ｍｏｄｅｌ ｔｏ ｄｅｃｏｍｐｏｓｅ ｔｈｅ ｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌｓ ｆｏｒ ｗｏｍｅｎ ａｇｅｄ ２０ ｔｏ ５０ ｂｅｔｗｅｅｎ １９８０ ａｎｄ ２０１３ ｉｎｔｏｔｈｒｅｅ ｐａｒｔｓ：ｔｈｅ ａｇｅ?ｓｐｅｃｉｆｉｃ ｍｉｎｉｍｕｍ ｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌ， ｔｈｅ ｅｌａｓｔｉｃｉｔｙ ｏｆ ｔｈｅ ｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌｃｒｏｓｓ ａｇｅ，ａｎｄ ｔｈｅ ｏｖｅｒ?ｔｉｍｅ ｃｈａｎｇｅ ｏｆ ｔｈｅ ｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌ． Ｔｈｅ ｒｅｓｕｌｔｓ ｓｈｏｗ ｔｈａｔ ｔｈｅ ｍｉｎｉｍｕｍｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌ ｒａｎｇｅｓ ｆｒｏｍ １． ２ ｔｏ １． ７ ｙｅａｒｓ． Ｉｎｃｒｅａｓｉｎｇ ａｇｅ ｏｆ ｗｏｍｅｎ ｉｓ ａｓｓｏｃｉａｔｅｄ ｗｉｔｈ ｉｎｃｒｅａｓｉｎｇ ｍｉｎｉｍｕｍ ｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌ．Ｔｈｅ ｅｌａｓｔｉｃｉｔｙ ｃｕｒｖｅ ｃｒｏｓｓ ａｇｅ ｄｅｍｏｎｓｔｒａｔｅｓ ａｎ Ｓ?ｓｈａｐｅ，ｗｈｉｃｈ ｆｌａｔｓ ｂｅｔｗｅｅｎ ａｇｅ ２０～３０，ｉｎｃｒｅａｓｅｓ ｌｉｎｅａｒｌｙ ｂｅｔｗｅｅｎ ａｇｅ ３０～４５，ａｎｄ ｄｅｃｌｉｎｅｓ ｓｌｉｇｈｔｌｙ ａｆｔｅｒ ａｇｅ ４５．Ｆｉｎａｌｌｙ，ｔｈｅ ｔｉｍｅ ｅｆｆｅｃｔ ｏｎ ｔｈｅ ｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌ ｉｓ ｎｅｇａｔｉｖｅ ｂｅｔｗｅｅｎ １９８６ ａｎｄ １９９６ ｗｈｉｌｅ ｉｔ ｉｓ ｐｏｓｉｔｉｖｅ ｂｅｔｗｅｅｎ １９８０ ａｎｄ １９８５ ａｎｄ ｂｅｔｗｅｅｎ １９９７ ａｎｄ ２０１３．Ｔｈｅｓｅ ｆｉｎｄｉｎｇｓ ｍａｙ ｈｅｌｐ ｄｅｅｐｅｎ ｏｕｒ ｕｎｄｅｒｓｔａｎｄｉｎｇ ｏｆ ｔｈｅ ａｇｅ?ｓｐｅｃｉｆｉｃ ｐａｔｔｅｒｎ ａｎｄ ｔｉｍｅ ｆｌｕｃｔｕａｔｉｏｎ ｏｆ ｔｈｅ ｓｅｃｏｎｄ ｂｉｒｔｈ ｉｎｔｅｒｖａｌ ｉｎ Ｃｈｉｎａ．

 This study examines the trends in and the impact of birth spacing policy on the second birth interval in China since 1970s using the population monitoring data in 121 Chinese counties．The birth spacing policy plays a significant role in regulating people’ s fertility behaviors thus slowing down population growth in China．Specifically，changes in second birth intervals have gone through three stages，a long-term stability before 1990s，an increase from 1990 to 2005 and a decline since 2006， implying a dynamic relationship with the birth interval regulation．Conditions for continuing the current birth spacing policy aiming at later birth，longer interval and less children no longer exist．Thus，the focus on birth spacing needs to be switched from a policy orientation to a health orientation．

This study examines the trends in and the impact of birth spacing policy on the second birth interval in China since 1970s using the population monitoring data in 121 Chinese counties．The birth spacing policy plays a significant role in regulating people’ s fertility behaviors thus slowing down population growth in China．Specifically，changes in second birth intervals have gone through three stages，a long-term stability before 1990s，an increase from 1990 to 2005 and a decline since 2006，implying a dynamic relationship with the birth interval regulation．Conditions for continuing the current birth spacing policy aiming at later birth，longer interval and less children no longer exist．Thus，the focus on birth spacing needs to be switched from a policy orientation to a health orientation．

In preparing for fertility policy adjustment and implementing the “Two-child Policy for Couples One of Which Has No Siblings”，a national fertility intention survey was conducted in 29 provinces in China in August 2013. Survey results indicate that，currently，the ideal number of children is 1.93 in China. The reported ideal number of children in regions with 1 child，1.5 and 2 children policies are 1.84，1.98 and 2.01 respectively. For the couples both of which have no siblings，one of which has siblings and both of which have siblings，the reported ideal numbers of children are 1.79，1.83 and 1.95 respectively. For the couples one of which has no siblings with one child，the reported ideal number of children is 1.81. The overall sex ratio of reported ideal numbers of children is 104 males per 100 females in China. The sex ratio is 128 for those whose ideal number of children is 1 and 102 for those whose ideal number of children is 2. For the couples one of which has no siblings with one child，59% are“uncertain”about the birth timing of next child，20.5% plan to give a birth in one year，12.1% plan to give a birth in two years and 8.4% plan to have one in three years. Adjustment of family planning policy will help narrow the gap between fertility intention and fertility behavior，and it is highly unlikely that a nation-wide birth heaping would occur if the“Two-child Policy for Couples One of Which Has No Siblings”is well implemented.