The motivation to breastfeed: a fit to the opponent-process theory?

The opponent-process theory, a dynamic model of acquired motivation presented by Solomon and Corbit (1974), was applied to the process of breastfeeding. A modified form of the Nowlis Mood Adjective Checklist (MACL, Nowlis, 1965, 1970) and a discomfort measure were used in assessing through recall the affective course predicted by the theory. The data were analyzed using multivariate analysis of variance (MANOVA) and correlational procedures. Results were highly significant: Women who breastfed for relatively long periods recalled positive affective responses while the baby was at breast and a subsequent negative or dysphoric response. The additional characteristics of acquired motivation, habituation, and withdrawal, were also evidenced in the data. As a control for possible confounding demand characteristics inherent in the methodology, a sample of childless women was surveyed using an "as-if" form of the same questionnaire. Very little similarity to the breastfeeders was found in the pattern of responses yielded by this group. It was concluded that our major findings are quite likely free of influence from this source.