Using a sample of couples drawn from the three provinces of Guangdong, Shandong, and Shaanxi, we investigated whether couples' increasing freedom to choose whom to marry influenced the timing of first birth in rural China during the four decades before the 1990s. The shortening of first-birth intervals in the period is found to be associated with the shift from arranged to free-choice marriages. The association is attributed largely to increased intimacy and coital frequency after marriage together with postponement of age at first marriage.