A prospective study was made of 441 pregnant victims of automobile accidents, in which 69 wore lap belts and 372 were unrestrained. There was no significant increase in either maternal or fetal mortality associated with lap belt restraint. The absence of maternal or fetal protection is discussed; the advantage of lap belt restraint in nonpregnant occupants appears to be nullified in pregnancy by the uterine compression produced by the snubbing action of the lap belt. It is concluded that there are no disadvantages of lap-belt restraint for pregnant travellers, and that the prevention of ejection provides a clear indication for its use. The lap belt should be secured low across the bony pelvis, not over the mid- or upper-fundus. When available, the lap belt and shoulder harness combination is recommended.