To investigate whether Russia's dramatic fertility changes pre- and post-Soviet times were due primarily to tempo effects, as has been argued recently, or to quantum effects, this study standardizes for factors that distort conventional fertility indexes. A time series spanning 1978–93 of period parity-progression ratios for the Russian Federation is constructed applying the PADTFR technique, which takes into account age, parity, and time elapsed since the birth of the previous child, to data from the Russian micro census of February 1994 (2.8 million maternity histories). Both the fertility rise of the 1980s and the fertility fall of the early 1990s are found to be primarily due to changes in the probability of a second birth. The impact of tempo on the conventional TFR is significant, but of relatively minor magnitude in comparison to changes in the quantum of fertility. The social and economic context in which the fertility change took place is described.