A total of 182 infertile patients undergoing in-vitro fertilization (IVF)-embryo transfer were randomly assigned into two groups. Eighty-seven patients (group A) underwent 97 treatment cycles and had 87 embryo transfer procedures followed by a 24 h period of bed rest. Ninety-five patients (group B) underwent 102 treatment cycles and had 93 embryo transfer followed by a 20 min period of bed rest. There were no statistically significant differences seen between the groups with respect to age, duration and causes of infertility and number of previous fertility treatments. The clinical and biological procedures were identical in both groups, the only difference being the length of bed rest. There were 21 pregnancies in group A (pregnancy rate per embryo transfer: 24.1%) while in group B there were 22 (pregnancy rate per embryo transfer: 23.6%). There were four spontaneous miscarriages (19%) and three twin pregnancies (14.2%) in group A, while in group B there were four spontaneous miscarriages (18.1%) and three twin pregnancies (13.6%). None of these values was statistically significant (P > 0.05). This study shows that a 24 h period of bed rest following embryo transfer is not associated with a better outcome of the IVF-embryo transfer when compared with a 20 min rest period. Prolonged bed rest does not appear to influence the implantation rate after IVF-embryo transfer.