There are many questions about the relationship between pregnancy and exercise. This article presents an overview of published works on a) exercise and problems with conception, with the focus on amenorrhea and miscarriage, b) exercise and pregnancy, highlighting the influence of exercise on maternal metabolism, cardiovascular and respiratory function, c) exercise and the developing embryo / foetus, with the focus on placental formation / growth, substrate availability and foetal hyperthermia, d) exercise and the labour / delivery process, with the emphasis on preterm labour, as well as e) exercise and the postpartum period, with the focus on neonatal outcome, maternal recovery after parturition and lactation. It concludes with recent recommendations and precautions associated with exercise during pregnancy, as well as shortcomings in available information. In general, literature does not seem to support the concerns about prenatal exercise, but rather shows that both mother and foetus benefit when the mother is involved in moderate exercises during pregnancy. Indications are that the benefits will only be experienced in full by women who, within reasonable limits, continue to exercise throughout their pregnancy.