Reproductive outcomes in women exposed to solvents in 36 reinforced plastics companies. I. Menstrual dysfunction.

Recent studies have suggested that exposure to styrene monomer and other solvents is associated with menstrual disturbances. This is the first U.S. study to evaluate the effects of exposure to styrene on dysmenorrhea, intermenstrual bleeding, secondary amenorrhea, menstrual blood clots, and hypermenorrhea. A comprehensive questionnaire was administered to 1,535 blue-collar workers. Multiple logistic regression analyses did not reveal a positive association between styrene exposure and any menstrual abnormality. Risk factors associated with menstrual disturbances included chronic illness with secondary amenorrhea (p less than or equal to .005), nulliparity with both decreased blood clots (p less than or equal to .005) and hypermenorrhea (p less than or equal to .001), smoking with blood clots (p less than or equal to .005), and age with hypermenorrhea (p less than or equal to .001). The overall prevalences of menstrual disorders were 14% for dysmenorrhea, 16% for intermenstrual bleeding, 7% for secondary amenorrhea, 40% for menstrual blood clots, and 31% for hypermenorrhea.