This paper examines the evolution of out-of-wedlock conceptions and births over the last four decades. Increases in conception outside of marriage only partially account for increases in the illegitimacy rate: controlling for age at pregnancy, being born one year later increases the probability of being single at first conception by 0.9 percentage points, while the probability of being single at first birth rises by 0.5 additional percentage points. The incidence of shotgun (post- conception) marriage among those conceiving out of wedlock decreased sharply, but the rate is not affected by the level of planning of the pregnancy nor is driven by non-users of modern contraception. However, women in marriage markets (defined by race, religion, and age) with high modern contraceptive use and who conceive outside marriage are less likely to give birth out of wedlock. The trend over time is significantly steeper when the level of modern contraceptive use in the woman’s market is considered, suggesting that the spread of the pill contributed to reduce the rate of increase of out-of-wedlock motherhood.