This study aimed to evaluate the effects of application of transcutaneous electrical nerve stimulation (TENS) at low and high frequencies to the abdomens of Swiss mice throughout pregnancy. Thirty Swiss mice received TENS throughout pregnancy. They were separated into three groups (n=10): placebo, low-frequency TENS (LF group) and high-frequency TENS (HF group). The pregnant mice were weighed on Days 0, 7, 14 and 20 to verify weekly weight gain by two-way analysis of variance. The numbers of fetuses, placentas, implantations, resorptions and major external fetal malformations on Day 20 were analysed using the Kruskal-Wallis test. No significant differences were observed between the placebo and TENS groups (P>0.05).
In this study, the application of low- and high-frequency TENS to the abdomens of pregnant mice did not cause any negative or major teratogenic effects.