Ultrasound evaluation of the stomach and gastric emptying in pregnant women at term: a case-control study

Minerva Anestesiol. 2016 May;82(5):543-9. Epub 2015 Nov 10.


Background: This study aims to assess the rate of gastric emptying in pregnant women in the third trimester scheduled for elective caesarean section (CS), in view to highlight the aspiration risk.

Methods: A prospective case-control study, with the approval of the Ethics Committee, was performed. At term pregnant women (group A) scheduled for CS and volunteer controls were recruited (group B). The ultrasonographic measurement of the antral area was performed, after a standardized meal, with a Convex probe. The antrum was displayed in the sagittal or parasagittal projections in the right upper quadrant, medial to the mid-clavicular line. The diameters of the antrum were measured and then the antral area was calculated. The measurements were conducted at 10 (T1), 90 (T2) and 240 (T3) minutes from the meal. Anthropometric data were collected for each patient.

Results: In group B, antrum distention was observed already after 10 minutes from the meal, and then a gradual decrease in the antral area until 4 hours after the meal was registered. On the contrary, in group A (at term pregnant) there was an initial smaller increase of antral area, followed by a greater increase that lasts up to 90 minutes, and finally a delayed and smaller reduction.

Conclusions: In pregnant women at term, the stomach does not seem to be able to expand immediately after the meal. The transit of food is completed later than in not pregnant women. The ultrasound of the stomach allows identifying delays gastric emptying and highlighting patients at risk of aspiration.

MeSH terms

  • Adult
  • Case-Control Studies
  • Cesarean Section
  • Eating
  • Elective Surgical Procedures
  • Female
  • Gastric Emptying / physiology*
  • Humans
  • Pneumonia, Aspiration / etiology
  • Pregnancy
  • Pregnancy Trimester, Third / physiology
  • Prospective Studies
  • Stomach / diagnostic imaging*
  • Stomach / physiology
  • Time Factors
  • Ultrasonography