Research and design
This is a prospective, randomized, double-blind controlled trial approved by the Institutional Ethics Committee of Anhui Women and Child Health Care Hospital (No. 2017(10)) in accordance with the Declaration of Helsinki, and written informed consent was obtained from all participants in the trial. The study was registered at Chictr.org.cn on 29/05/2020 with the registration number ChiCTR2000033356 (