The Effect Of Exposure To Electromagnetic Fields In Daily Life On The Early Pregnancy

[Background] With the science and technology developing, people are widely exposed to electromagnetic fields(EMFs). At present studies on the biological effects of EMFs are focused on toxic effects of genes, mutations, cancer and damage to embryonic development, as well as life quality related indexes, such as memory, sleep quality. As the reproductive function is essential to human health and the quality of future population, more and more public concerns focused on whether EMFs could affect the health of the reproductive function. A large amount of animal studies examined the relationship between EMFs and the embryo development or the outcome of pregnancy. Because of the difference in animal species, frequency and intensity of exposure among animal studies, the results were controverciaL Most of the epidemiological studies on the effect of EMFs exposure were conducted in subjects with occupational exposure, while controvercies in results also existed. Evidences of the effects of exposure to electromagnetic radiation in daily life were limited.[Objective] To explore the effect of EMFs exposure on the embryo development in early pregnancy, and to explore the threshold of the intensity of EMFs with regard to its effect on embryo development, if any existed.[Methods] A cross-sectional study was conducted in pregnant women who were screened by eligible criterias. The basic demographic characteristics, reproductive and contraceptive history, electrical appliances using, residence remodeling, occupational history, surrounding factories and other information were collected by trained interviewer with structured questionnaire. All participants were asked to wear a magnetic field measuring meter for 24 "typical" hours to obtain the quantitative parameters of EMFs exposure. The development of embryo was examined by type-B ultrasonic, pathological examination and apoptosis assay. The correlation between EMFs and electrical appliances using and embryo development during early pregnancy were explored after controlling the gestational age, smoking history, drinking history and other potential confounders. t-test, chi-square test and multiple linear regression and logistic regression were used in the analysis.[Results] A total of 149 subjects were investigated, and all of which had type B-ultrasound and pathological examination.131 subjects carried the EMFs meter as required. We analyzed the apoptosis magnitude of the embryonic tissue of 91 subjects.Among the parameters of EMFs, only the correlation between the length of embryo bud and the 75th percentile EMFs exposure was statistically significant. After dividing subjects into two groups by the distribution of the 75th percentile by the cutoff point of 0.77mG, the higher exposure was associated with a shorter embryo bud.We analyzed the cumulative effect by dividing the subjects into two groups according to the time-weighted parameters. No cumulative effect of EMFs was found on the embryo development.There were 8 subjects who had a slight pathological change in embryonic tissue, while no correlation was found between EMFs exposure and pathological change. The apoptosis assay results were not correlated with EMFs exposure as well.[Conclusions] In summary, EMFs daily life exposure was associated with embryo bud development in early pregnancy, but no cumulative effect was found.