Little, Bert and Patterson, Margaret A. Embryofetal effects of neuroelectric therapy (NET). Electro and Magnetobiology. 15(1):1-8, 1996.
After obtaining IRB approval by the University of Texas Southwestern Medical Center, virgin Spraque-Dawley female rats were mated with Spraque-Dawley male rats. All rats were fitted with 2 ear identification tags, including controls who did not receive any CES, to provide equal nociception and stress. All rats were permitted to move freely within their cages. The treated rats were divided into 3 groups and given CES 1 hour daily throughout their pregnancy at either 10, 100, or 1,000 Hz, 1 volt, 0.125 mA, at a 0.22 mS pulse width via alligator clips attached to the ear tags. On day 18 of pregnancy, the dams were killed by guillotine or with ether, and cesarean section was performed immediately. Fetuses were counted and the uteri were examined for evidence of embryo resorption. The fetuses were immediately placed in 10% fomalin. Xeroradiographic surveys of posteroanterior and lateral views of each fetus were taken and evaluated for cranial, rib, vertebral, or long bone abnormalities. After thorough external examination, autopsies were performed under a dissecting microscope to evaluate the palate, heart and major vessels, lungs, liver, kidneys, ureters, and bladder. Statistical analysis included the use of x2, analysis of variance, and Newman-Keuls multiple group comparisons test. 844 fetal rats were evaluated.
The detailed external examinations under light microscopy revealed no obvious neural tube defects, limb reduction deformities, or anterior abdominal wall abnormalities in the controls or any of the treatment groups. Skeletal surveys of the fetal rats revealed no vertebral column, rib, or long bone deformities. Comparison between groups revealed more pregnancy resorptions and fewer offspring in all treatment groups as compared to the control group, with the difference reaching significance in the 1,000 Hz treatment group. Average fetal weights were inversely proportional to frequency and were significantly different among groups. Fetal brain weight followed a similar pattern of reduction, except that weights were not significantly different between the medium and highest frequency treatment groups.
In their discussion, the authors stated that while the incidence of congenital anomalies was zero, the reason pregnancy resorptions were increased may be due to the CES treated rats being more complacent. Their behavior resembled the effects of CES in humans, even in this aggressive population well known for their violence. The treated rats were not as active as the controls, accordingly it is possible that food intake was lowered in the treatment group, a reasonable implication given the reduction in fetal weights. The authors concluded that CES may be embryolethal in the very early stages of pregnancy in the rat and might cause some miscarriages, but there is no evidence of fetotoxic effects. The relevance of these findings to humans is unknown.