Abstract

This epidemiological study examined the effect of chemical exposures, physical stress, and working conditions on fetal death at various stages of pregnancy. The study population is based on over 22 000 pregnancies occurring in 56 000 women from the Montréal area interviewed between 1982 and 1984. To be eligible for inclusion in this study, the pregnancy must have occurred to a woman working at least 30 hours per week at the time of conception.

Of these cases, 22% were terminated by spontaneous abortion. An excess of spontaneous abortions among women employed in the service sector, and of spontaneous abortion and stillbirths among saleswomen, was observed after correcting for confounding variables. Nursing assistants and attendants, food and beverage servers and workers employed in the manufacture of electrical and metal goods also exhibited an excess of spontaneous abortions. The excesses in spontaneous abortions are attributed to the lifting of heavy loads, excessive exertion, working a standing position for long periods, work schedules of over 45 hours per week, rotating or changing work shifts, and exposure to cold, noise, and vibration. The study also observed a risk of late spontaneous abortion among operating room nurses, radiology technicians, and workers in the agricultural and horticultural sectors, all of whom may be exposed to foetotoxic agents.