Marital Status and Reproductive Performance in Kipsigis Women: Re-evaluating the Polygyny-Fertility Hypothesis

The effects of marital status on fertility and offspring survivorship are examined with data on six marriage cohorts of Kipsigis women, agro-pastoralists of south western Kenya. Neither marriage order, nor the average number of co-wives married to a man during a woman's reproductive years, is associated with completed family size, nor with any of the components of reproductive performance. The mechanisms whereby polygyny might potentially lower the reproductive performance of polygynously married women in the Kipsigis and other populations are discussed in some detail, with particular reference to resource shortages, sexual and economic favouritism, the observance of post partum taboos, disease, husband's age, co-wife co-operation, education, sterility, and age at menarche and marriage.