There are significant gaps in our understanding of how the experience of an unintended pregnancy affects subsequent contraceptive behavior. Our objective was to explore how three measures of pregnancy preferences—measuring timing-based intentions, emotional orientation, and planning status—were related to the uptake of postpartum family planning within one year after birth. Additionally, we tested whether the relationship between each measure and postpartum family planning uptake differs by parity, a key determinant of fertility preference. Adjusted hazards regression results show that the timing-based measure, specifically having a mistimed pregnancy, and the emotional response measure, specifically being unhappy, were associated with contraceptive uptake in the extended postpartum period, while those related to pregnancy planning, as measured by an adapted London Measure of Unplanned Pregnancy, were not. This effect differed by parity; high parity women were consistently the least likely to use contraception in the postpartum period, but the effect of experiencing an unwanted pregnancy or having a mixed reaction to a pregnancy was significantly stronger among high parity compared to low parity women. Greater attention to the entirety of women’s responses to unanticipated pregnancies is needed to fully understand the influence of unintended pregnancy on health behaviors and outcomes for women and their children.