Extremely low frequency electromagnetic field exposure affects fertilization outcome in swine animal model

Modern society continuously exposes the population to electromagnetic radiation, the effects of which on human health, in particular reproduction, are still unknown. The aim of this research was to assess the effect of acute (1h) exposure of boar spermatozoa to a 50Hz extremely low frequency electromagnetic field (ELF-EMF) on early fertility outcome. The effect of intensities ranging from 0 to 2mT on morpho-functional integrity of capacitated spermatozoa was examined in vitro. The oviducts containing or without spermatozoa were then exposed to the minimum in vivo, TD50, and maximum intensities determined in vitro, 4h before ovulation. The effects of ELF-EMF on spermatozoa in terms of early embryo development were evaluated after 12h and 6 days. It was found that in vitro ELF-EMF >0.5mT induced a progressive acrosome damage, thus compromising the ability of spermatozoa to undergo acrosomal reaction after zona pellucida stimulation and reducing the in vitro fertilization outcome. These effects became evident at 0.75mT and reached the plateau at 1mT. Under in vivo conditions, the ELF-EMF intensity of 1mT was able to compromise sperm function, significantly reducing the fertilization rate. In addition, the exposure of oviducts to fields ≥ 0.75mT in the absence of spermatozoa was able to negatively affect early embryo development. In fact, it was found to cause a slowdown in the embryo cleavage. In conclusion, it was demonstrated how and at which intensities ELF-EMF negatively affect early fertility outcome in a highly predictive animal model.