Puzzles and further explorations in the interrelationships of successive births with husband's income, spouses' education and race.

When fertility is examined in the detail of individual parity progressions and birth-order transitions, important interactions between the effects of income and education are seen. Among the findings are: the negative effect of education on fertility is stronger at all parities for less educated compared to more highly educated women. Additional income has a more positive effect for more highly educated than for less educated women. For women with 0-8 years of education the effect of more income is positive when the family has no children but negative thereafter, but for college-educated women the effect of more income is positive. And additional income has a less positive (more negative) effect on fertility among nonwhites than among whites.