In the last post, we discussed the biological and social mechanisms that may help us understand one of the most sought-out benefits of babywearing: calmer, happier babies who cry less. Though physiological processes involved in close physical contact help calm the infant and regulate their sleep cycles – thereby leading to a reduction in crying – there may be an important social process involved as well: caregiver responsiveness. How caregivers respond to their babies shows variation across cultures. In Western industrialized cultures for example, infant-caregiver communication is characterized by high levels of vocal and visual interaction and prompt responses to infants’ cues. However, one of the potentially most important forms of responsiveness is breastfeeding on-demand in response to early hunger cues. Higher rates of on-demand breastfeeding are seen in the proximal care cultures that are also known for their low levels of infant crying.[i]
Does breastfeeding decrease crying?
If so, this would be great news for babywearers, as one of the widely cited benefits of wearing your baby is that babywearing facilitates breastfeeding. Skin-to-skin contact is proven to facilitate lactation and longer duration of breastfeeding,[ii] thus leading to protection against childhood infection, decreased risk of childhood obesity and diabetes, and decreased risk of ovarian and breast cancer.[iii] The health benefits of breastfeeding are undisputed, but what is the connection between babywearing, breastfeeding, and crying?
Actually, current evidence on the relationship between breastfeeding and crying is inconclusive, given that breastfed infants have been found to show greater distress, less smiling, laughing, vocalization, and lower sooth-ability than formula-fed infants.[iv] However, the specific mechanism for crying reduction may not be in breastfeeding itself, but rather in the specific type of breastfeeding responsiveness that is practiced in proximal care cultures: breastfeeding on-demand. Breastfeeding on-demand refers to feeding infants in response to early hunger cues (e.g., rooting, squirming) as opposed to late cues (i.e., crying).[v] Breastfeeding on-demand – in some cultures – can occur up to four times per hour.[vi]
What is the role of physical contact in breastfeeding on-demand?
As mentioned previously, proximal care cultures that are known for being in physical contact with their infants for the majority of the day – and are also known for their decreased levels of infant crying in comparison with most Western, industrialized societies – also practice breastfeeding on demand. Is this culturally-mediated combination of factors enough evidence to suggest that breastfeeding on-demand may actually cause decreased crying? One study found that feeding on-demand – rather than to a schedule – effectively increased infants’ display of early hunger cues, suggesting that breastfeeding in response to cues motivates infants to use other forms of communication rather than crying.[vii] However, studies on this topic are few and far between…We still have much to learn!
In hopes of elucidating the connection between physical contact, responsive breastfeeding, and crying, the UCSD Developmental Lab is conducting research to look at maternal feeding behaviors here in Western culture. Preliminary research shows that breastfeeding in response to early hunger cues – rather than in response to crying or feeding according to a schedule – is predicted by mother-infant physical contact. Specifically, mothers documented each feeding session with their child over three consecutive days, noting whether they were in physical contact with the baby before the onset of feeding and the reason for each feeding (crying, hunger cues, or schedule). The prediction was that mothers would be more likely to initiate feedings in response to early hunger cues (e.g., rooting, squirming) if they were in close physical contact with the baby before deciding to feed. Whereas if they were farther away from their child (e.g., baby sleeping in a crib or playing on the floor), mothers would be more likely to realize their child was hungry from crying, as the lack of close contact would potentially make mothers less aware of the more subtle hunger cues. Analyses are still in process, but preliminary results show that there is a strong association between mother-infant physical contact and responsiveness to hunger cues.
Though this study is not testing the effect on crying yet, there are still exciting implications for babywearing-related public health interventions. Specifically, feeding on-demand promotes the development of healthy, self-regulated eating behaviors[viii] and is associated with decreased risk for childhood obesity.[ix] In our adult-run society, we often forget the extraordinary competencies that infants have and attempt to manage their biological functions through scheduled feeding times and naptimes. However, at as young as eight weeks, infants can regulate their breastmilk intake[x] and adjust the volume that they drink in response to the energy content.[xi] Breastfeeding in response to infants’ cues of hunger and satiation – rather than according to an adult-determined schedule – recognizes this impressive ability of young infants to self-regulate food intake according to their needs.
Stay tuned for more details on this research and click here to get involved!
This Guest Blog was written by Emily E. Little, M.A.
Emily is a doctoral candidate in developmental psychology at University of California, San Diego. Her dissertation research examines the social mechanisms underlying the benefits of babywearing, including how increased mother-infant physical contact facilitates higher maternal responsiveness. Her research program more broadly investigates culturally-mediated mother-infant communication, and she has collected data on early teaching in Vanuatu, infant emotional displays in Bolivia, and breastfeeding patterns in Guatemala. She is also specializing in anthropogeny, or the study of human origins, through UCSD’s Center for Academic Research and Training in Anthropogeny (CARTA), which has added an evolutionary perspective to her interests in culture, mother-infant interaction, and babywearing. She is passionate about making a positive contribution in the communities where she works, not just in San Diego – where she volunteers as a Volunteer Babywearing Educator in training with Babywearing International – but also at her international fieldsites, where she volunteers at community health centers and raises money for maternal and infant health services.
[i] Richman, A. L., Miller, P. M., & LeVine, R. A. (1992). Cultural and educational variations in maternal responsiveness. Developmental Psychology, 28(4), 614.
[ii] Anderson, G. C., Chiu, S. H., Dombrowski, M. A., Swinth, J. Y., Albert, J. M., & Wada, N. (2003). Mother‐Newborn Contact in a Randomized Trial of Kangaroo (Skin‐to‐Skin) Care. Journal of Obstetric, Gynecologic, & Neonatal Nursing, 32(5), 604-611.
[iii] Victora, C. G., Bahl, R., Barros, A. J., França, G. V., Horton, S., Krasevec, J., … & Group, T. L. B. S. (2016). Breastfeeding in the 21st century: epidemiology, mechanisms, and lifelong effect. The Lancet, 387(10017), 475-490.
[iv] de Lauzon-Guillain, B., Wijndaele, K., Clark, M., Acerini, C. L., Hughes, I. A., Dunger, D. B., … & Ong, K. K. (2012). Breastfeeding and infant temperament at age three months. PLoS One, 7(1), e29326.
[v] Hodges, E. A., Hughes, S. O., Hopkinson, J., & Fisher, J. O. (2008). Maternal decisions about the initiation and termination of infant feeding.Appetite, 50(2), 333-339.
[vi] Barr, R. G., Konner, M., Bakeman, R., & Adamson, L. (1991). Crying in! Kung San infants: a test of the cultural specificity hypothesis.Developmental Medicine & Child Neurology, 33(7), 601-610.
[vii] Saunders, R. B., Friedman, C. B., & Stramoski, P. R. (1991). Feeding preterm infants. Journal of Obstetric, Gynecologic, & Neonatal Nursing,20(3), 212-220.
[viii] Wright, P., Fawcett, J., & Crow, R. (1980). The development of differences in the feeding behaviour of bottle and breast fed human infants from birth to two months. Behavioural Processes, 5(1), 1-20.
[ix] Birch, L. L., & Fisher, J. O. (1998). Development of eating behaviors among children and adolescents. Pediatrics, 101(Supplement 2), 539-549.
[x] Li, R., Fein, S. B., & Grummer-Strawn, L. M. (2010). Do infants fed from bottles lack self-regulation of milk intake compared with directly breastfed infants?. Pediatrics, 125(6), e1386-e1393.
[xi] Fox, M. K., Devaney, B., Reidy, K., Razafindrakoto, C., & Ziegler, P. (2006). Relationship between portion size and energy intake among infants and toddlers: evidence of self-regulation. Journal of the American Dietetic Association, 106(1), 77-83.