CONTEXT: Demographic phenomena occur within social contexts and, therefore, should be studied as social processes. However, how to conceptualize and measure the social worlds that individuals inhabit has been the subject of debate.

METHODS: Data from a study conducted in Mali in 1996-1997 are used to explore the social networks of Bamanan women and their impact on fertility decisions. Ordinary least-squares and logistic regression techniques are employed to examine the relationship between selected household and social network characteristics and two fertility measures: children ever born and ever-use of contraceptives.

RESULTS: Household characteristics do not have a significant effect on either outcome, whereas network attributes do. The more prominently conjugal kin are represented in a network, the fewer children a woman has ever had; however, fertility increases if the husband or unrelated older women are part of the network. Ever-use of contraceptives is elevated if the woman participates in a credit scheme, and rises as the proportion of network members located outside the village increases; it declines sharply as the proportion of network members who are conjugal kin increases, and is significantly elevated if the woman's mother is present. Network effects on fertility are much more pronounced for women aged 30 or older than for younger women, and network effects on contraceptive use are markedly different for younger and older women.

CONCLUSIONS: Programs should consider not only women's individual and household characteristics, but also their larger social networks. Additionally, programs should be designed for specific age-groups, given the different network effects on older and younger women.