MOTOR‐CAR ACCIDENTS DURING PREGNANCY: 2

calculation suggests that the number of women with pregnancies of more than 20 weeks' gestation who were occupants of cars involved in casualty accidents in Victoria, in the three years studied, was in excess of 400. Of these only 26 entered the authors' series. However, taken at face value, the authors' Table I can be condensed as in my Table I. If one disregards the case in which the belt status is uncertain, there are 14 belted subjects and three unbelted subjects with uterine rupture or placental separation. No published information is available about the belt wearing habits of women in the later part of pregnancy. The Victorian belt-wearing law exempts persons who secure certificates of a medical reason for not wearing a belt, but there is no general exemption for pregnancy. A weighted mean of 68% for lap-sash belt use for Victoria in the three-year period can be derived from the data of McKenzie and Milne. S If pregnant women made about the same use of belts, then-on the hypothesis that the belt had no effect on the uterus-these 17 cases would be expected to occur in I I belted and six unbelted women. This is not significantly different from the numbers observed, which thus may simply be reflecting belt usage. Crosby and Costiloe carried out a prospective study of lap-belted and unrestrained pregnant occupants of cars involved in severe accidents. The maternal and fetal mortalities were not significantly different. They encountered two cases of ruptured uterus in 208 occupants, both in the un belted group, These considerations would suggest caution in accepting the conclusion of Pepperell et alii, on the evidence adduced, that wearing a seat belt "may well" increase the risk of uterine rupture or placental separation. The conclusion, whether correct or not, raises the question of seat belt wearing during pregnancy, but the authors make no recommendation as to the advice an antenatal patient should get from her doctor. It must be kept in mind that belt wearing, besides effecting an overall reduction in fatalities and injuries, alters the pattern of injuries. A car accident causing a placental separation in a belt wearer might, in an unrestrained occupant, cause massive maternal injuries and fetal death. In the authors' 26 cases in which it is known whether or not a belt was worn, non-wearers contributed all five maternal deaths and 12 fetal losses, compared with 14 fetal losses by belt wearers. Should the patient be advised not to wear a belt? Surely not, in the light of the prospective survey ofCrosby and Costiloe?