The impact of first birth interval length on economic success over time

This research investigates the impact of first birth interval length on economic success over time among a sample of 2,361 white, continuously married couples. Data from 1970 and 1975 are analyzed by path analysis and analysis of variance. The major findings include the following. (1) First birth interval length has only a weak bivariate relationship to economic success as measured by husband's income and family income. (2) The bivariate relationship appears to increase in strength over time. (3) The apparent increase in strength of the bi-variate relationship is due to some of the more successful members of the premaritally pregnant group misrepresenting the length of their first birth interval, (k) Controlling for the effects of selected intervening variables, especially: husband's educational attainment; husband’s occupational rank; wife's educational attainment; wife's age at marriage; and, duration of marriage, greatly reduces the strength of the relationship of first birth interval length to economic success. (5) The impact of first birth interval length on economic success is greater among a sub-sample of recent parents. (6) Comparing the results of the recent parents with the results of the entire sample serves to reconcile previous research in this area.