A systematic review and meta-analysis of the impacts of glyphosate on the reproductive hormones

Worldwide use of glyphosate is constantly increasing and its residues are detected in drinking water, agriculture, and food products. There are controversial data regarding the potential reproductive adverse effects of glyphosate herbicide. Therefore, we conducted a systematic review and meta-analysis on the studies in which the alteration of at least one sexual hormone including testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol was reported as a measured outcome in rats. In November 2020, 284 articles were screened, of which eight were eligible for the meta-analysis. An overall considerable effect of glyphosate exposure was found on decreasing of testosterone (7 studies, WMD = − 1.48 ng/mL; 95% CI, − 2.34 to − 0.61; P = 0.001), LH (3 studies, WMD = − 2.03 mIu/mL; 95% CI, − 3.34 to − 0.71; P = 0.003), and FSH (3 studies, WMD = − 2.28 mIu/mL; 95% CI, − 5.12 to 0.55; P = 0.115). According to our results, glyphosate intake could have major effects on the health of reproductive system. Consequently, strict monitoring of the residual glyphosate content in the drinking water, agricultural crops, and food products is necessary.