To determine the effect of a continuous, 60 Hz, nighttime magnetic field exposure on sleep outcomes in young women sleeping at home.
Women were studied during two 5-night measurement periods: 1) exposure (0.41-1.21 µT); 2) sham exposure (ambient magnetic field levels, 0.001-0.50 µT). 19 subjects completed one measurement period and 58 completed both. Subjects were between 20-40 years of age, had regular mentrual cycles, were not taking oral contraceptives, and had not breastfed or been pregnant during the previous year. Both measurement periods started two days after the luteinizing hormone surge of the menstrual cycle.
Exposure duration: continuous for 5 nights
|Exposure duration||continuous for 5 nights|
|Setup||exposure directed at the center of the pillow|
|Sham exposure||A sham exposure was conducted.|
|magnetic flux density||0.001 µT||minimum||measured||-||0.001 µT - 0.5 µT; ambient feld|
|magnetic flux density||0.5 µT||maximum||measured||-||ambient field|
|magnetic flux density||0.41 µT||minimum||measured||-||0.41 µT - 1.21 µT exposure field|
|magnetic flux density||1.21 µT||maximum||measured||-||exposure field|
During the sham exposure (ambient magnetic field) subjects slept on average 6 hours and 58 minutes, with a sleep efficiency of 88.3 %. During the exposure period they slept on average 7 hours and 1 minute, with a sleep efficiacy of 88.4 %. Sleep outcomes were not significantly different between the exposure and sham exposure.