摘要
In recent years,more and more attention has been paid to normal childbirth.The World Health Organization(WHO),International Confederation of Midwives(ICM),Chinese Maternal and Child Health Association(CMCHA)have actively advocated normal childbirth[[1],[2],[3]].It is proved that normal childbirth can improve birth outcomes.
基金
This manuscript was supported by Beijing Natural Science Foundation(Grant No.7222106).
