Using retrospective data from Korea, multivariate log-linear analyses were used to determine if the sex of a child influences the probability of it being breastfed, or if it influences the number of months he/she was breastfed. In Korea the likelihood of a woman not breastfeeding a child is very small. The fact that a woman is without living sons increased the average odds of not breastfeeding by 1.55 times. The absence of living sons has the strongest effect of any of the predictor variables used. The highest predicted conditional odds of not breastfeeding are for women with female infants, who live in rural areas, have less than 3 children of which none are boys, and who do not use oral contraceptives. The lowest predicted conditional odds of a woman not breastfeeding are for a city dweller, with 3 or more children of which at least 1 is a boy, who uses the pill, and whose infant is a boy. Although oral contraceptive use is significant for deciding how long to breastfeed, the direction of its effect is not what was expected had it affected lactation physiologically. Apparently, social factors are operative which make pill users more likely to breast feed than non-users. 1 possible explanation for this is that Korean women are aware of the fertility-suppressing effects of lactation and are using breastfeeding as a deliberate form of birth control. The fact that the effect of pill use becomes progressively stronger the longer that women breastfeed lends further support to this explanation. The effect of sex of child is not significant in determining the duration he/she will be breastfed. This study indicates support for the contention that Korean women are aware of the contraceptive effects of lactation, and that their decisions of breastfeed are affected by their preference for sons.

作者：R J, Nemeth；J M, Bowling

来源：Journal of biosocial science 1985 年 17卷 4期