Greater demands have been imposed by present-day management practices on the modern dam with gilts being bred at younger ages and lower levels of back fat. This has raised questions over whether current rearing feeding practices and low pregnancy feeding regimes may have adverse influences on lifetime reproductive performance. The objectives of this experiment were to compare the reproductive performance of sows given different feeding regimes during rearing and pregnancy. Data previously reported from the experiment have shown that the weight and back fat depth of the gilt can be manipulated by feeding regime during rearing and pregnancy (Simmins et al. 1989). Sows reared on lower feed levels were more prolific in their first two litters but they also had longer farrowing intervals (Edwards et al. 1989). Further results up to the fourth parity are described here.