The effects of radiofrequency exposure on male fertility: A systematic review of human observational studies with dose-response meta-analysis

Abstract

Overview

The World Health Organization (WHO) is gathering evidence about the health outcomes related to exposure to radiofrequency electromagnetic fields (RF-EMF), focusing on research areas previously identified as priorities for safe exposure guidelines. This systematic review synthesizes data from human observational studies, guided by the WHO handbook for guideline development and the COSTER conduct guidelines, to assess the effects of RF-EMF exposure on male fertility.

Methods

• A comprehensive search was performed across MEDLINE, Embase, Web of Science, EMF Portal, and grey literature sources.
• Quantitative human observational studies involving adult males assessing sperm concentration, morphology, motility, total sperm count, and time to pregnancy were included.
• Data extraction and risk of bias assessment were performed in duplicate. Certainty was evaluated using OHAT and GRADE tools. Meta-analysis was conducted where feasible.

Findings

• Nine studies were included (seven involving the general public, two occupational).
• General Public Studies:
  • Duration of mobile phone use: Evidence is very uncertain regarding effects on sperm concentration, morphology, progressive motility, and total sperm count due to very low-certainty evidence. Statistical significance was rarely found. Risk of multiple biases noted.
  • Position of phone: Limited or no effect found for front-pocket carrying on fertility indicators. At least one study found statistical significance, but all were susceptible to high risk of bias.
  • Other RF-EMF sources: One study found little/no effect from computers/electric devices on sperm parameters, but it had high risk of bias.
• Occupational Studies:
  • Only two studies found; results were too heterogeneous to pool. High risk of bias present in both.

Discussion

The evidence base is dominated by assessments of mobile phone-related RF-EMF exposure, with few studies considering phone position or other sources. Overall, the relationship between RF-EMF exposure and male fertility outcomes remains very uncertain due to very low certainty and high risk of bias across studies.

Conclusion

Overall, there is a connection between RF-EMF exposure and potential health risks to male fertility, but the certainty of evidence is currently very low. Where data allowed for meta-analysis, certainty was graded as very low, and most included studies had significant risk of bias. Current research does not allow strong conclusions about the effects of RF-EMF on male fertility. More rigorously designed prospective studies with improved exposure measurement and statistical methods are required to clarify effects on male reproductive health.