Objective: To assess the degree of full stomach of full-term parturients and predict the risk of gastric reflux and aspiration. Methods: A total of 169 full-term parturients with a gestational age of ≥ 36 weeks were selected and divided into two groups according to fasting time < 6 h as full stomach group and fasting time ≥ 6 h as empty stomach group. Bedside ultrasound was used to determine the long diameter

short diameter

and cross-sectional area of the gastric antrum in the right decubitus position at different time points. When the cross-sectional area of the right side decubitus > 10.3 cm2 was defined as a full stomach under ultrasound. At the same time

their age

height

weight

gestational age

fasting time

and type of food eaten at the last meal were recorded. Results: With the prolongation of fasting time

the gastric antrum cross-sectional area of parturients gradually decreased and tended to be stable. There was statistical significance in gastric antrum cross-sectional area between full stomach group and empty stomach group (P<0.05). There were 46 parturients in full stomach group

including 18 (39.13%) with full stomach under ultrasound and 28 (60.87%) with empty stomach. Among 123 parturients in empty stomach group

1 (0.81%) had full stomach under ultrasound and 122 (99.19%) had empty stomach. The Kappa coefficient was 0.469 (95%CI=0.341-0.643

P<0.001). The cross-sectional area of gastric antrum of pregnant women with empty stomach under ultrasound was not correlated with age

gestational age

height

weight and BMI (P >0.05). Conclusion: It is not accurate to judge the degree of full stomach of parturients based on fasting time. For parturients with fasting time < 6 h

bedside ultrasound can reduce unnecessary clinical intervention and improve patient comfort. For parturients with fasting time ≥ 6 h

bedside ultrasound can detect potential satiety patients

improve the safety of anesthesia

and is a fast

convenient and reliable new gastric satiety assess-ment method.