 900 parturient who underwent CS under general anesthesiaGA , intraspinal anesthesia included epidural anesthesiaEA and combined spinal-epidural anesthesiaCSEA, which were divided into 3 groups: Morbid Obesity group n300 with body mass index BMI 40 kgm2 , severe Obesity group n300 with 30 kgm2BMI 40 kgm2 and non-Obesity groupn300 with BMI30 kgm2. Findings Between January 1, 2013 and September 30, 2016, a total of 1000 women met inclusion criteria and 900 women received allocated intervention. All patients were divided into three groups: Morbid Obesity groupn300, Severe Obesity groupn300 and non-Obesity groupn300 according to body mass index BMI 40 kgm2, 30 kgm2BMI 40 kgm2 and BMI30 kgm2.900 patients completed the protocol and related data were analysed. 