Hirschman C, Butler M
Demography. 1981 Feb;18(1):39-54.
Analysis of the 1973 National Survey of Family Growth shows a continued downward trend in breast feeding by successive cohorts of American mothers. The downward trend is evident in both measures of incidence (ever-breast feeding) and duration of breast feeding for first and higher-order births. For all cohorts higher-order births are less likely to be breast fed than first births. However, breast feeding of higher-order births is typically of a longer duration. Differentials in breast feeding reveal strong associations with indicators of social class; women who are college graduates, who work as professionals, and who are married to professional husbands are most likely to breast-feed their infants. Differentials in average duration of breast feeding are often reversed from differentials in ever-breast feeding.
对1973年全国家庭成长调查的分析表明，美国母亲的连续几代人母乳喂养率持续呈下降趋势。这种下降趋势在母乳喂养发生率（曾经母乳喂养）和初产及多产母乳喂养持续时间这两项指标中都很明显。对于所有几代人来说，多产的母乳喂养可能性低于初产。然而，多产的母乳喂养时间通常更长。母乳喂养的差异显示出与社会阶层指标有很强的关联；大学毕业、从事专业工作且丈夫为专业人士的女性最有可能母乳喂养她们的婴儿。母乳喂养平均持续时间的差异往往与曾经母乳喂养的差异相反。
