2.1. General Information
congenital malformations, fetal distress
PRETERM DELIVERY, CARDIOVASCULAR DISEASE, FETAL DISTRESS
This study selected 160 healthy singleton mothers aged 20–35 who underwent elective cesarean section in Wuhu Second People's Hospital from August, 2019, to August, 2021. Participants with cardiovascular disease, fetal congenital malformations, fetal distress and preterm delivery, and participants who have intraspinal anesthesia contradictions were excluded from this study. According to the method of random number table, the patients were equally divided into 