exposure to extremely low frequency electromagnetic fields during pregnancy and the risk of spontaneous abortion: a case-control study

background: exposure to extremely low frequency electromagnetic fields is increasingly common, but the potential influence on pregnant women has not been thoroughly investigated. methods: in this case-control study, 58 women who had an unexplained spontaneous abortion at < 14 weeks gestation and 58 matched pregnant women >14 weeks gestation were enrolled in 2012. the women completed the questionnaire, which was used to collect data about socioeconomic and obstetric characteristics, medical and reproductive histories. then, to evaluate the extremely low frequency electromagnetic fields , we determined the magnitude of electromagnetic fields in the  participants´ houses by an exposure level tester (3d emf tester/ model: elf-828; taiwan).the instrument covers a limited frequency range (30 hz to 3 khz). results: the magnitude of extremely low frequency electromagnetic fields in the participants´ houses was significantly different between the two groups ( p <0.001). conclusions: extremely low frequency electromagnetic fields exposure is probably related to early spontaneous abortions.