Context Numerous women of childbearing age are exposed
occupationally to organic solvents. Previous retrospective studies have
reported conflicting results regarding teratogenic risk.
Objective To evaluate pregnancy and fetal outcome following
maternal occupational exposure to organic solvents.
Design A prospective, observational, controlled study.
Setting An antenatal counseling service in Toronto, Ontario.
Patients One hundred twenty-five pregnant women who were exposed
occupationally to organic solvents and seen during the first trimester
between 1987 and 1996. Each pregnant woman who was exposed to organic
solvents was matched to a pregnant woman who was exposed to a
nonteratogenic agent on age (±4 years), gravidity
(±1), and smoking and drinking status.
Main Outcome Measure Occurrence of major congenital malformations.
Results Significantly more major malformations occurred among
fetuses of women exposed to organic solvents than controls (13 vs 1;
relative risk, 13.0; 95% confidence interval, 1.8-99.5). Twelve
malformations occurred among the 75 women who had symptoms temporally
associated with their exposure, while none occurred among 43
asymptomatic exposed women (P<.001). (One malformation
occurred in a woman for whom such information was missing.) More of
these exposed women had previous miscarriage while working with organic
solvents than controls (54/117 [46.2%] vs 24/125 [19.2%];
P<.001). However, exposed women who had a previous
miscarriage had rates of major malformation that were similar to
exposed women who had no previous miscarriage.
Conclusions Occupational exposure to organic solvents during
pregnancy is associated with an increased risk of major fetal
malformations. This risk appears to be increased among women who report
symptoms associated with organic solvent exposure. Women's exposure to
organic solvents should be minimized during pregnancy. Symptomatic
exposure appears to predict higher fetal risk for