Objective: To observe the effects of exposure to extremely low frequency electromagnetic fields (ELF EMFs) on pregnant mice and development of offsprings.
Methods: Female mice were exposed to 50 Hz, 1.2 mT electromagnetic fields during the whole pregnant period (8 h/d). The body weight of dams, delivery and development of offsprings were observed and measured.
Results: The increase of body weight of exposed dams (29.0%) was significantly slower than that of the control group (47.8%) during late pregnancy period (P < 0.05). The producing rate of exposed group was 60% of that of control group. Miscarriage, fetal loss and externally malformed fetus appeared in exposed group. The average number of offsprings of each exposed mouse was significantly decreased (11 +/- 1.6 vs 7 +/- 2.0, P < 0.05) and 11 for control group. Regarding the development of offspring, the body weight of prenatally exposed offsprings was increased more slowly than that of the control in the first two weeks after birth (P < 0.05). Developmental manifestations including eye opening [(252 +/- 24) h] and tooth eruption [(336 +/- 19) h] presented later in exposed offspring [(226 +/- 12), (319 +/- 15) h, respectively] (P < 0.05).
Conclusion: Exposure to ELF EMFs during pregnancy period can cause adverse effects on pregnancy of female mice and development of offsprings.