• Reproductive ecology;
  • Breastfeeding patterns;
  • Breastfeeding structure;
  • Lactational amenorrhea;
  • Infant growth


Recent research has shown that significant variation in breast-feeding behavior exists among natural fertility populations, all of whom have been characterized as practicing “on-demand” breastfeeding. A number of recent prospective studies have contributed to a better understanding of breastfeeding structure and of its consequences for population differences in fertility. Currently, there is a growing interest in quantifying the complex environmental and biocultural interactions which influence that structure; in other words, in establishing an ecology of breastfeeding.

In this paper, a carefully structured retrospective study of breastfeeding behavior among nomadic Turkana is used to identify environmental, biobehavioral, and socioeconomic factors associated with variation in breastfeeding frequency among Turkana women. In agreement with the results of a prospective study conducted as part of the same research, the age (growth) and physical development of nurslings show significant correlations with breastfeeding frequency. Maternal physical status, the depth of the maternal social network, and, to a lesser degree, rainfall patterns are also significant. All of these factors appear to influence breastfeeding through their effects on maternal participation in herding activities and related absences from camp. Finally, the study also presents new strategies for collecting and utilizing retrospective data, which are notoriously unreliable and difficult to classify according to operational definitions recently developed for prospective studies. Results of the present study suggest methods by which the quality and reliability of recall data may be enhanced. © 1995 Wiley-Liss, Inc.