Huang, Minyuan
Luo, Dan
Wang, Zhanghua
Cao, Yongmei
Wang, Hua
Bi, Fengying
Huang, Yunxiang
Yi, Luxi
Funding for this research was provided by:
Major Scientific and Technological Projects for collaborative prevention and control of birth defects in Hunan Province (2019SK1010, 2019SK1011)
The Scientific Research Project of Health Commission of Hunan Province (A20182001)
Article History
Received: 7 December 2019
Accepted: 3 April 2020
First Online: 15 April 2020
Ethics approval and consent to participate
: Health Commission of Hunan Province granted us permission to use data from Hunan maternal and child health information reporting and management system.
: Not applicable.
: The authors declare that they have no competing interests.