This paper considers how the diffusion of oral contraception to young unmarried women affected the number and parental characteristics of children born to these women. In the short term, pill access caused declines in fertility and increases in both the share of children born with low birthweight and the share born to poor households. In the long term, access led to negligible changes in fertility while increasing the share of children with college-educated mothers and decreasing the share with divorced mothers. The short-term effects appear to be driven by upwardly mobile women opting out of early childbearing, while the long-term effects appear to be driven by a retiming of births to later ages. These effects differ from those of abortion legalization, although we find suggestive evidence that pill diffusion lowered abortions. Our results suggest that abortion and the pill are on average used for different purposes by different women, but on the margin, some women substitute from abortion toward the pill when both are available.