Family formation changed dramatically over the 20th century in the United States. The impact of these changes on childbearing has primarily been studied in terms of nonmarital fertility. However, changes in family formation behavior also have implications for fertility within marriage. The authors used data from 10 fertility surveys to describe changes in the timing of marital childbearing from the 1940s through the 21st century for non-Hispanic White and non-Hispanic Black women. Based on harmonized data from the Integrated Fertility Survey Series, the results suggest increasing divergence in fertility timing for White women. A growing proportion of marriages begin with a premarital conception; at the same time, an increasing proportion of White women are postponing fertility within marriage. For Black women, marital fertility is increasingly postponed beyond the early years of marriage. Evaluating the sequencing of marriage and parenthood over time is critical to understanding the changing meaning of marriage.