Yoshida Y et al. · 1995
Researchers exposed pregnant rats to microwave radiation at the same frequency used in microwave ovens (2,450 MHz) and measured blood flow to the placenta. They found that microwave exposure significantly reduced placental blood flow and disrupted multiple pregnancy hormones including estradiol and progesterone. This matters because reduced placental blood flow can harm fetal development and pregnancy outcomes.
Nelson BK et al. · 1994
Researchers exposed pregnant rats to radiofrequency radiation (10 MHz) combined with an industrial solvent called 2-methoxyethanol to see if the combination caused more birth defects than either exposure alone. They found that when combined, these exposures produced enhanced developmental damage to limbs and digits in rat fetuses, particularly when exposure occurred on day 13 of pregnancy. This suggests that EMF radiation can amplify the harmful effects of certain chemical exposures during pregnancy.
Guberan E et al. · 1994
Swiss researchers studied whether shortwave radiation exposure during pregnancy affects the gender ratio of babies born to female physiotherapists, following up on a Danish study that found fewer male births. They surveyed 2,846 Swiss physiotherapists about their radiation exposure and children's gender, analyzing 1,781 pregnancies. The study found no difference in gender ratios between exposed and unexposed mothers, contradicting the earlier Danish findings.
Sarkar S, Ali S, Behari J · 1994
Researchers exposed mice to 2.45 GHz microwave radiation (the same frequency used in WiFi and microwave ovens) at power levels considered safe for public exposure. After 4-7 months of daily exposure, they found distinct changes to DNA patterns in both brain and testis tissue compared to unexposed mice. The study is significant because it detected genetic alterations at exposure levels currently deemed safe by international radiation protection guidelines.
Lokhmatova SA, · 1994
Russian researchers exposed male rats to 3 GHz radiofrequency radiation (similar to some WiFi frequencies) for 2 hours daily over 4 months at power levels of 0.25 mW/cm². They found significant damage to the testes and sperm-producing structures, with effects persisting even 4 months after exposure ended. This suggests that prolonged RF exposure at relatively low power levels can cause lasting reproductive harm in male animals.
Ouellet-Hellstrom R, Stewart WF · 1993
Researchers surveyed over 42,000 physical therapists to examine whether occupational exposure to microwave diathermy equipment affected pregnancy outcomes. They found that women who used microwave diathermy units during the six months before conception or during the first trimester had a 28% higher risk of miscarriage, with risk increasing to 59% for those with the highest exposure levels (20 or more uses per month). Interestingly, shortwave diathermy equipment showed no increased risk.
Fukui Y, Hoshino K, Inouye M, Kameyama Y · 1992
Japanese researchers exposed pregnant mice to 2.45 GHz microwave radiation (the same frequency used in microwave ovens and WiFi) during a critical brain development period. They found that 20 minutes of exposure caused brain damage, reduced brain weight, and altered brain cell density in developing offspring. The effects were similar to heating the animals in hot water, suggesting the damage came from the microwaves heating brain tissue.
Larsen AI · 1991
Danish researchers studied 54 physiotherapists who gave birth to children with congenital malformations and 247 who had healthy babies, examining whether exposure to high-frequency electromagnetic radiation during the first month of pregnancy increased birth defect risk. They found no statistically significant link between EMF exposure and birth defects (odds ratio 1.7 with a confidence interval that included no effect). This suggests that the high-frequency electromagnetic devices commonly used in physiotherapy practice may not increase the risk of congenital malformations.
Larsen AI, Olsen J, Svane O · 1991
Danish researchers studied 586 pregnancies among physiotherapists exposed to high-frequency electromagnetic radiation from medical equipment. They found that mothers with high EMF exposure gave birth to significantly fewer boys (only 23.5% compared to the normal 51%), and male babies born to exposed mothers had lower birth weights. The study suggests that EMF exposure may selectively affect male reproductive outcomes.
Nelson BK et al. · 1991
Researchers exposed pregnant rats to radiofrequency radiation and an industrial solvent called 2-methoxyethanol, both separately and together, to see how they affected developing babies. When used together, the combination caused birth defects in 76% of litters compared to just 14-30% when each agent was used alone. This suggests that RF radiation can amplify the harmful effects of certain chemicals during pregnancy.
Spiers DE, Baummer SC · 1991
Scientists exposed developing quail eggs to microwave radiation for 8 hours daily and found it accelerated embryo growth by 9-61% through heating effects. The faster development occurred without apparent abnormalities, demonstrating that microwave exposure can alter biological processes even when organisms seem normal.
