Oral intake during labor has been a controversial subject for some time. Recently, the topic has reemerged in social media and obstetrical discussion following a press release from the American Society of Anesthesiologists (ASA) highlighting a medical student presentation at the ASA Annual Meeting in San Diego in October 2015.1 These researchers analyzed 385 studies published in 1990 or later, focusing on women who gave birth in a hospital. They also had access to the ASA Closed Claims Project database. They found that healthy women have an extremely low risk of aspiration during labor and birth, including surgical birth. There were no cases of death due to aspiration associated with labor and delivery in the United Kingdom between 2000 and 2005 compared with the risk of death due to aspiration in the 1940, 1.5 per thousand. There was 1 case of aspiration associated with labor and delivery in the United States between 2005 and 2013. This aspiration occurred in an obese woman with preeclampsia. The press release does not state whether this woman survived. The researchers theorized that the decrease in death caused by aspiration in labor and delivery is likely due to the increased use of epidural and spinal anesthesia, the vanishing use of anesthesia by mask, and the reduced need for endotracheal tube placement.1
Sharts-Hopko2 presents the recommendations of several professional organizations in her review of the literature of the subject. This information is presented in Table 1.
There have been multiple literature reviews on the subject. Several are highlighted in this column. King and colleagues3 found that there is little modern evidence to support the denial of oral nutrition in labor for all women. These authors focused on the laboring woman's right to choose her own interventions for childbirth based on current evidence.3 Sharts-Hopko2 reviewed the literature with particular attention to the effects of oral intake during labor including energy needs, ketosis, hyponatremia, maternal stress, vomiting, and obstetrical outcomes. She concluded that studies show that food ingestion may prolong labor, but there was no association with adverse outcomes for mothers or infants.2
The latest Cochrane review on the subject of oral intake during labor examined 19 studies. Five of these studies met criteria for review, involving 3130 women.4 The review found no benefits or harms in the policies restricting oral intake in laboring women who are at low risk for needing anesthesia for labor or birth. The conclusion of the review is that women should be free to eat and drink in labor as they wish.4 The authors of the Cochrane review also concluded that since there are no studies looking specifically at women at increased risk of complications, there is no evidence supporting restrictions on oral intake in this group either.4 The reviewers specifically call for studies exploring women's views on the subject as well as investigation into the risks and benefits of liquid and solid intake by laboring women.4
Why is oral intake for laboring women, especially of solid food, restricted by most hospitals in the United States? The original research was published by Curtis Mendelson in 1946. Mendelson5 audited the medical records of 44 016 women giving birth in the New York Lying-In Hospital from 1932 to 1945. Sixty-six of these women experienced pulmonary aspiration, an incidence of 0.15%. Forty women experienced aspirations of liquid and 5 of aspirated food. Two of the women died. Both of the deaths were due to aspiration of food. As often happens in the field of obstetrics, Mendelson's recommendation that all oral intake in labor be restricted and denied was rapidly adopted in the United States and the United Kingdom.2 In this time period in the United States and the United Kingdom, general anesthesia was more widely used in childbirth, anesthesia was not always administered by specialists (Mendelson5 notes that new and inexperienced interns are often assigned to administer obstetrical anesthesia), and endotracheal intubation was common.2 Aspiration of fluid was more common in Mendelson's audit, but the 2 deaths were due to aspiration of food. Some hospitals at the time chose to restrict all oral intakes for laboring women, and some chose to restrict only solid food. This variance in restriction exists today.
There has been little research in the years following Mendelson's article in 1946. The Cochrane Collaboration located only 5 high-quality studies.4 King and colleagues3 reviewed 20 studies but found that definitions were not standardized, making it difficult to compare research. Study formats ranged from randomized controlled trials to observational reports. There was a wide range in a parameter as basic as the definition of active labor.3
Despite the presentation at the ASA meeting and the decision of the ASA to present the findings to the public in a press release, the ASA House of Delegates passed an updated report on October 28, 2015, affirming the restriction of solid foods for laboring women at any stage of labor.6 The ASA arrives at its Practice Guidelines by a combination of literature review, expert opinion including anesthesiologists and nonanesthesia physicians, opinions from practitioners likely to be affected by the guidelines, and formal survey of members of the ASA.6
While reaffirming the previous guidelines that allow liquids for laboring women at low risk for cesarean birth and restricting all solid foods in labor, there has been slight movement in the opinions of the consultants and the surveyed anesthesiologists.6,7 The survey questions were different from 2007 to 2016, making some comparisons difficult. In 2007, 16% of the consultants and nearly 30% of surveyed anesthesiologists disagreed with the statement that oral intake of liquids during labor does not increase maternal complications.7 At that time, more than 9% of consultants and 4% of anesthesiologists surveyed disagreed with the statement that oral intake of solids during labor increased maternal complications.7 In the guidelines published in 2016, less than 2% of consultants and less than 12% of anesthesiologists surveyed disagreed with the statement that the oral intake of clear liquids may be allowed for uncomplicated laboring patients.6 In these guidelines, less than 4% of consultants and less than 7% of anesthesiologists surveyed disagreed with the statement that solid foods should be avoided in laboring patients.6 The anesthesia community has moved toward acceptance of clear liquids for laboring women unlikely to need anesthesia for birth, but support for the prohibition of solid food for laboring patients has remained constant. This is despite the lack of published reports studying oral intake in labor. The Committee Opinion on Oral Intake During Labor published by the American Congress of Obstetricians and Gynecologists in 2009 reflects the ASA Practice Guidelines and the only reference cited for the opinion is the ASA Practice Guidelines.8
The argument can be made that there have been no cases of death due to asphyxia during labor because of the restriction of oral intake during labor. It can also be argued that with a 30% cesarean birth rate in the United States, very few women are truly at low risk for needing anesthesia. However, the risk of asphyxia even in 1946 was 0.15% and is certainly lower today due to the reasons cited earlier in this column. Restriction of oral intake is not common practice in birth centers or labor and births in the home setting, and, currently, we have no way of knowing whether there have been any cases of asphyxia in these settings except perhaps anecdotally.
Restriction of oral intake during labor may actually be harmful for women. Labor and birth increase the energy needs of the woman, but metabolic processes seem to adjust to fit individual needs.4 There is little published literature looking at the nutritional needs of laboring women.2 Women who ate solid food vomited more but did not have increased lengths of labor or poorer outcomes than women who did not in a study of women laboring in a birth center in Michigan.9 Drinking isotonic energy drinks did not seem to affect the duration of labor in healthy low-risk nulliparous women.10 There does not appear to be enough evidence either way at this point to justify restriction of oral intake, especially with the extremely small risk of harm.
Much more research and study are needed, examining risks and benefits, and exploring what women want to do during labor. Most women will self-regulate if given the choice, and most women will reduce their intake of solid food as labor progresses.9
What can nurses do when confronted with hospital policies that are not supported by current evidence, especially when professional organizations mandate restriction of oral intake during labor? Sharts-Hopko2 suggests a framework for nurses including advocacy for the establishment of interdisciplinary working groups to explore and review policies that restrict oral intake for laboring women. For institutions that have already relaxed their policies, she suggests that nurses take a proactive approach, advising women about the types of foods that are appropriate so that women can incorporate this advice into birth plans, and informing women of the potential risks associated with the intake of solid food during labor.2 This is education and nursing care that is more appropriately performed in the office setting prior to labor. However, many women come to the hospital in labor without this information and the labor and delivery nurse may be the primary source of knowledge for the laboring woman and family.
There will be no changes in the current policies and guidelines until an evidence base is built. Nurses and interdisciplinary teams can begin developing this base with observational studies, qualitative work with women, and randomized controlled trials in the appropriate settings. Nurses can help make labor more comfortable and intuitive for woman, and build on the innate wisdom woman have in labor, allowing laboring women to self-regulate oral intake as they labor.
-Jackie Tillett, ND, CNM, FACNM
Lead Midwife
Aurora Midwifery and Wellness Center
Aurora Health Care
Milwaukee, Wisconsin
-Chasity Hill, BSN, RN
Student Nurse-Midwife
Midwifery Program
Marquette School of Nursing
Milwaukee, Wisconsin
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