Okay, now I’m moving from my foodie thread to a mommy thread, but I couldn’t pass up commenting on recent research by Ruth Feldman of Bar Ilan University in Israel [1]. Feldman measured oxytocin levels in pregnant women during their first and third trimesters, and then again in their first post-partum month. These oxytocin levels were correlated with evidence of mother-infant bonding, such as how much the mother gazed at her infant, used “motherese” to speak to her infant, and maintained constant and affectionate touching.

Oxytocin is a multi-purpose hormone that is also released during orgasm or nursing an infant.

Feldman’s first-trimester oxytocin levels were highly predictive of maternal bonding behaviors. In addition, mothers with high oxytocin levels were more likely to sing “special songs” to their infant, check on their infant frequently, and think frequently about the infant’s safety and future.

A great deal of research in animals, especially species of voles, shows that oxytocin is an important hormone for both pair bonding and parenting behaviors, but Feldman’s study extends this body of knowledge to humans.

One has to wonder about the implications of such a study. Do we check oxytocin levels during a first trimester and try to intervene with those who are “low” in order to avoid later child abuse? Why does one woman have more oxytocin than another? Do the circumstances surrounding her pregnancy (planned versus accidental; stable, loving partnership or not) influence her oxytocin levels?

On a related note, anthropologists have pointed out that holding a child on the left side of the body is a human universal [2]. This seems to have a calming effect, because the baby can hear the mother’s heartbeat. It’s interesting to see how frequently celebrity moms don’t do this….should we measure oxytocin levels?

1. Feldman, R. (2007). Evidence for a neuroendocrinological foundation of human affiliation: Plasma oxytocin levels across pregnancy and the postpartum period predict mother-infant bonding. Psychological Science [epub ahead of print]. For a copy, contact Catherine West of APS at cwest@psychologicalscience.org

2. Bolton, R. (1978). Child-holding patterns. Current Anthropology, 19, 134-135.