of its "eagerly anticipated" study using rats and mice, conducted over some ten years. This report concludes after the review with an updated statement that "there is clear evidence that male rats exposed to high levels of radio frequency radiation (RFR) like that used in 2G and 3G cell phones developed cancerous heart tumors.... There was also some evidence of tumors in the brain and adrenal gland of exposed male rats. For female rats, and male and female mice, the evidence was equivocal as to whether cancers observed were associated with exposure to RFR". An analysis of preliminary results from the study argued that due to such issues as the inconsistent appearances of "signals for harm" within and across species and the increased chances of false positives due to the multiplicity of tests, the positive results seen are more likely due to random chance. The full results of the study were released for peer review in February 2018. A 2021 review found "limited" but "sufficient" evidence for radio frequencies in the range of 450 MHz to 6,000 MHz to be related to gliomas and acoustic neuromas in humans, however concluding also that "... the evidence is not yet sufficiently strong to establish a direct relationship". Conclusions could not be drawn for higher frequencies due to insufficient adequate studies. Fertility and reproduction A decline in male sperm quality has been observed over several decades. Studies on the impact of mobile radiation on male fertility are conflicting, and the effects of the radio frequency electromagnetic radiation (RF-EMR) emitted by these devices on the reproductive systems are currently under active debate. A 2012 review concluded that "together, the results of these studies have shown that RF-EMR decreases sperm count and motility and increases oxidative stress". A 2017 study of 153 men that attended an academic fertility clinic in Boston, Massachusetts found that self-reported mobile phone use was not related to semen quality, and that carrying a mobile phone in the pants pocket was not related to semen quality. A 2021 review concluded 5G radio frequencies in the range of 450 MHz to 6,000 MHz affect male fertility, possibly affect female fertility, and may have adverse effects on the development of embryos, fetuses and newborns. Conclusions could not be drawn for higher frequencies due to insufficient adequate studies. Electromagnetic hypersensitivity Some users of mobile phones and similar devices have reported feeling various non-specific symptoms