Intended for healthcare professionals


Effect of food intake during labour on obstetric outcome: randomised controlled trial

BMJ 2009; 338 doi: (Published 25 March 2009) Cite this as: BMJ 2009;338:b784

Effect of food intake during labour on obstetric outcome. A response

We wish to extend our congratulations to O’Sullivan et al on the content of their paper. However, we would like to add a note of caution to the broader conclusions that might be made following a reading of the PICO version.

The paper demonstrates that feeding obstetric patients did not alter the incidence of vaginal delivery. We believe that it is important to emphasise that feeding parturients is not without risk.

The successful reduction in maternal morbidity and mortality is a triumph of modern medicine. One turning point in this reduction was the recognition and subsequent prevention of ‘Mendelson’s syndrome’.

Aspiration of gastric contents and resulting chemical pneumonitis occurs in 1 in 3216(1) all general anaesthetics , has a mortality of 30 percent and accounts for up to 20 percent of all deaths attributable to anaesthesia(2). The obstetric population has a tenfold risk of failed intubation when compared with the general population. This translates to a frequency of 1 in 250 and a more recent report suggested an increase to 1 in 130(3), attributed to the reduced exposure to obstetric general anaesthetics amongst trainee anaesthetists.

Mendelson’s syndrome is more common in the obstetric population(4)and is associated with failed intubation. This has led to the increasing use of regional anaesthesia in obstetric emergencies. The result is a significant reduction in obstetric deaths. General anaesthesia is however, still inevitable in some cases and emergency caesarean section remains unpredictable. What is predictable is that; non fasted obstetric patients have a much greater risk of gastric aspiration than the fasted normal population.

If low risk women are offered a light, easily digestible diet during labour they should be advised this will not improve their obstetric and neonatal outcome(5), but should they be advised that it may do them harm?

Dr D. R. Windsor (StR2 in Anaesthesia)

Dr M. M. McSwiney (Consultant in Anaesthesia)

Anaesthetic Department,
Cheltenham General Hospital,
GL53 7AN


1) Warner MA, Warner ME, Weber JG. Clinical significance of pulmonary aspiration during the perioperative period. Anesthesiology. 1993;78(1):56-62

2) Knight, P.R, Curtis L. Mendelson, M.D.: Aspiration Investigator. American Society of Anaesthesiologists Newsletter. Sept 1999;63(9)

3) Jenkins, J. G. Failed intubation during obstetric anaesthesia. British Journal of Anaesthesia. 1996;77:698.

4) Mendelson CL. The aspiration of stomach contents into the lungs during obstetric anesthesia. Am J Obstet Gynecol. 1946;52:191-205.

5) O’Sullivan G, Liu B, Hart D, Seed P, and Shennan A. Effect of food intake during labour on obstetric outcome: randomised controlled trial. BMJ 2009; 338: b784

Competing interests:
None declared

Competing interests: No competing interests

01 May 2009
David R. Windsor
StR2 Anaesthesia
Mike McSwiney
Cheltenham General Hospital, GL53 7AN