Q: Can I use electric blankets while we try to conceive (TTC) and during pregnancy?

A: The following are various reports on the use of electric blankets while TTC and during pregnancy:

• One report on users of electrically heated beds (electric blankets and heated waterbeds) found an increase in spontaneous pregnancy loss during seasons of use and concluded that either thermal or electromagnetic field effects might be involved in human reproductive wastage (Wertheimer N, Leeper E: Possible effects of electric blankets and heated waterbeds on fetal development. Bioelectromagnetics 7:13-22, 1986).
• A subsequent report by the same authors showed a similar seasonal variation in pregnancy loss associated with the use of ceiling heating coils, lending further credence to the possibility of an effect mediated by electric fields. (Wertheimer N, Leeper E: Fetal loss associated with two seasonal sources of electromagnetic field exposure. Am J Epidemiol 1989;129:220-4.)
• Others have also reported finding a small increase in risk of pregnancy loss associated with electric blanket use at the time of conception and in early pregnancy (Belanger K, Leaderer B, Hellenbrand K et al: Spontaneous abortion and exposure to electric blankets and heated water beds. Epidemiology 1998;9:36-42.).
• A report (published in abstract) on pregnant women with a history of subfertility found an association between electric blanket use and congenital urinary tract abnormalities (Li D-K, Checkoway H, Mueller BA. Electric blanket use in relation to the risk of congenital urinary tract anomalies among women with a history of subfertility. Teratology 1995;51:190.).
• However, an epidemiologic study in New York State did not find evidence that electric bed heating increased the risk of congenital defects or fetal loss (Dlugosz L, Vena J, Byers T et al: Congenital defects and electric bed heating in New York State: a register-based case- control study. Am J Epidemiol 135:1000-11, 1992. ; Jansson-E Re: "Congenital defects and electric bed heating in New York State: a register-based case-control study" Am J Epidemiol 137: 585-7, 1993.)