Authors: Desai N et al.
European Journal of Anaesthesiology, volume 43, issue 2, February 2026, pages 103–118,
This review examines gastric physiology and aspiration risk across pregnancy, labor, and the postpartum period, integrating contemporary evidence with practical implications for obstetric anesthesia. The authors address long-held assumptions about the “full stomach” in pregnancy and reframe fasting, aspiration risk, and airway management using physiologic data and gastric ultrasound.
Baseline gastric secretion and acidity are not altered by pregnancy. Gastric emptying of clear fluids is delayed in the first trimester compared with the nonpregnant state, but by the second and third trimesters there is no meaningful difference in gastric emptying of water or solids. In women scheduled for elective cesarean delivery, preoperative carbohydrate drinks as part of enhanced recovery pathways do not increase gastric antral cross-sectional area. Likewise, “sip-til-send” clear fluid strategies are noninferior to traditional fasting and improve patient comfort and satisfaction.
Labor represents a distinct physiologic state. In women without epidural analgesia, gastric emptying is delayed for both clear fluids and solids and is further impaired by systemic opioids. Epidural analgesia increases gastric emptying compared with unmedicated labor, although not to nonpregnant levels. Clear fluids are generally tolerated during labor, but solid food intake continues to pose concern.
In the postpartum period, gastric emptying of water returns to nonpregnant norms. The review highlights gastric ultrasound as a valuable adjunct in obstetric anesthesia, particularly for cesarean delivery under general anesthesia. Using the I-AIM framework (indication, acquisition, interpretation, medical management), obstetric anesthesiologists can qualitatively and quantitatively assess gastric contents. Specific antral cross-sectional area thresholds are provided to identify high-risk gastric volumes. When high-risk contents are identified, ultrasound findings may influence timing of surgery or anesthetic technique. When risk appears low, ultrasound may support less aggressive airway strategies or inform decision-making during failed intubation scenarios.
Key Points
Gastric emptying of clear fluids is delayed only in the first trimester; later pregnancy resembles the nonpregnant state.
Labor delays gastric emptying, especially with systemic opioids; epidural analgesia improves but does not normalize emptying.
Clear fluids are generally tolerated in labor, while solid food remains a concern.
Postpartum gastric emptying of water is similar to nonpregnant patients.
Gastric ultrasound using the I-AIM framework can meaningfully guide anesthetic and airway decisions in obstetrics.
Thank you to the European Journal of Anaesthesiology for allowing us to summarize and discuss this article.