Use of video display terminals during pregnancy and the risk of spontaneous abortion, low birthweight, or intrauterine growth retardation

Use of video display terminals (VDTs) during pregnancy among working women was examined using data from a large case-control study of spontaneous abortions (SAB) occurring in 1986-1987. The crude odds ratio for SAB and VDT use was 1.2 for use of less than 20 hours per week (95% CI = 0.88, 1.6) as well as for 20 hours or more (CI = 0.87, 1.5), with little change after adjustment for a variety of confounders. The effects of VDT use may vary by the gestational age at SAB, with stronger associations seen in earlier (less than or equal to 12 weeks) compared to later SABs. Use of VDTs within specific occupational categories was examined, yielding adjusted odds ratios varying from 0.5 to 1.7. The risk for low birthweight (LBW) among the control group also was not greatly elevated at either VDT use level, with adjusted ORs of 1.1 (0.52, 2.1) and 1.4 (0.75, 2.5), respectively. However, the risk for intrauterine growth retardation was somewhat elevated among women with greater VDT use (OR = 1.6, CI = 0.92, 2.9).