Written by Jennie Bever Babendure, PhD, IBCLC
The ever increasing rates of labor induction and augmentation have caused many to begin to ask if the use of synthetic oxytocin to start or augment labor may impact mothers and babies after birth. In an Acta Paediatrica article published online ahead of print, Ibone Olza-Fernandez and her colleagues asked this question by looking at neonatal feeding reflexes in relation to oxytocin dosage during labor1. In this small pilot study, researchers documented the total dose of oxytocin given during labor to induce or augment contractions in 20 first time mothers. On day 2 of life, and at least 1 hour after breastfeeding, they placed babies skin to skin with their mothers in biological nurturing positions to elicit Primitive Neonatal Reflexes, including those involved in breastfeeding. When 3 observers blind to the oxytocin dose coded videotapes of these 20 minute sessions, they found a significant correlation between higher doses of synthetic oxytocin during labor and the absence of sucking behavior in infants. In fact, many of the newborns whose mothers received higher doses of oxytocin spent a large part of the 20 minutes skin to skin crying.
When the authors later followed up with the mothers about breastfeeding status at 3 months, they found another surprising correlation: mothers who were exclusively breastfeeding at 3 months had received a lower average dose of oxytocin during labor than mothers who were not breastfeeding exclusively.
Findings of this study are limited in that this was a very small pilot of only 20 women, and all received oxytocin either to augment or induce labor, thus the study lacks an important control group of mothers who did not receive oxytocin. As such, the authors are careful to point out that the results should be interpreted with caution. The relationship found between oxytocin dose and infant suck in this study is a correlation only, and provides no evidence that higher doses of oxytocin caused the depression in sucking behavior. (Click this link for a great discussion of why we can’t say a correlation indicates cause.)
In addition, all study mothers received epidural anesthesia, thus the depressed sucking behavior could be related to maternal dose of anesthesia (which was not recorded), precipitating increased need for labor augmentation. However, as studies in rodents have shown reduced food intake in response to oxytocin injection, and previous clinical research has demonstrated an association between intrapartum oxytocin administration and risk of artificial feeding independent of epidural anesthesia, the idea that synthetic oxytocin might have an impact on breastfeeding behavior is an intriguing hypothesis that deserves further study2-8.
I joke that the picture below shows me ‘under the influence’ of oxytocin. If you look closely, I look just the tiniest bit love-crazed. Could oxytocin, a hormone that can inspire such intense bonding actually have a negative effect at high doses? I’ll keep a close watch as further research unfolds!
For more research commentary, check out Jennie’s new blog: www.breastfeedingscience.com
1. Olza Fernández I, Marín Gabriel M, Malalana Martínez A, Fernández-Cañadas Morillo A, López Sánchez F, Costarelli V. Newborn feeding behaviour depressed by intrapartum oxytocin: a pilot study. Acta Paediatrica 2012.
2. Arletti R, Benelli A, Bertolini A. OXYTOCIN INHIBITS FOOD AND FLUID INTAKE IN RATS. Physiology & Behavior 1990;48(6):825-830.
3. Jordan S, Emery S, Watkins A, Evans JD, Storey M, Morgan G. Associations of drugs routinely given in labour with breastfeeding at 48 hours: analysis of the Cardiff Births Survey. BJOG: An International Journal of Obstetrics & Gynaecology 2009;116(12):1622-1632.
4. Benelli A, Bertolini A, Arletti R. OXYTOCIN-INDUCED INHIBITION OF FEEDING AND DRINKING – NO SEXUAL DIMORPHISM IN RATS. Neuropeptides 1991;20(1):57-62.
5. Olson BR, Drutarosky MD, Chow MS, Hruby VJ, Stricker EM, Verbalis JG. OXYTOCIN AND AN OXYTOCIN AGONIST ADMINISTERED CENTRALLY DECREASE FOOD-INTAKE IN RATS. Peptides 1991;12(1):113-118.
6. Ounsted MK, Boyd PA, Hendrick AM, Mutch LMM, Simons CD, Good FJ. INDUCTION OF LABOR BY DIFFERENT METHODS IN PRIMIPAROUS WOMEN .2. NEURO-BEHAVIORAL STATUS OF INFANTS. Early Human Development 1978;2(3):241-253.
7. Ounsted MK, Hendrick AM, Mutch LMM, Calder AA, Good FJ. INDUCTION OF LABOR BY DIFFERENT METHODS IN PRIMIPAROUS WOMEN .1. SOME PERINATAL AND POSTNATAL PROBLEMS. Early Human Development 1978;2(3):227-239.
8. Wiklund I, Norman M, Uvnas-Moberg K, Ransjo-Arvidson AB, Andolf E. Epidural analgesia: Breast-feeding success and related factors. Midwifery 2009;25(2):E31-E38.
I am a mother of 2 active boys and an Assistant Research Professor in the College of Nursing and Health Innovation at Arizona State University. As breastfeeding researcher, I am constantly scanning the literature for articles that guide my research and inform my clinical practice. One of my goals is to increase the evidence base of our profession as lactation consultants. I feel it is important for lactation professionals to be aware of and contribute to breastfeeding research, especially when so much of it is fascinating! As an ongoing contributor to Lactation Matters, it is my hope that you will find the articles I highlight as interesting and informative as I do, and that you will use them to guide you in the important work of lactation professionals and breastfeeding advocates.