Effects of extremely low frequency electromagnetic fields during foetal life on adulthood learning in male rat

Our environment is exposed to electromagnetic fields by development and industrialization of life. The aim of this investigation was to evaluate the effects of extremely low frequency electromagnetic fields (5 and 25 Hz) during fetal life on adulthood learning in male rat. In this study forty eight Sprague ِDawley pregnant rats (150±20g) were divided into six groups of eight: control, sham, and 5 or 25Hz and 50 or 500µT. Duration of exposure was 4 hours per day (continuously from 8 to 12 A. M.) from first day to 15th day of gestation. We evaluated learning, body weight, brain weight, brain volume, brain weight to body weight ratio and brain density of 60 days-old male offsprings. The learning task was performed by shuttle box in the form of one-way active avoidance conditioning. The number of conditioning responses and latency periods was recorded. Data was statistically analyzed by Kruskal-wallis test. Fetal life exposure to ELF EMF (25Hz/50µT) improved learning, decreased body weight and increased brain weight to body weight ratio in male rat (P<0. 05). Fetal life exposure to 25 Hz/500 µT, 5 Hz/500 µT and 5 Hz/50 µT increased body weight. Fetal life exposure to ELF EMF (25Hz/50µT) could improve learning in male rats.