Victoria Ifeoluwa Adisa, Precious Jesutofunmi Ashonibare, Cecilia Adedeji Adegbola, Tunmise Maryanne Akhigbe, Oluwakemi Rebecca Kolawole, Isaac Ayomide Omole, Fabrael Batale Fidelis, Adetomiwa Ezekiel Adeogun, Rebecca Promise Oluwole, Bolaji Aderibigbe Akorede, Babatunde David Ogunkola, Adebayo Oluwafemi Adekunle, Suliat Adenike Hassan, Sulaimon Bayonle Ajeigbe, Sulaiman Shuaibu Mansur, Precious Adeoye Oyedokun, Victory Jesutoyosi Ashonibare, Olayinka Emmanuel Adelowo, Racheal Ibukun Oyesetan, Ayoola A Abimbola Oladipo, Roland Eghoghosoa Akhigbe
JBRA Assist. Reprod. 2025; 29 (4):764-782
Received February 12, 2024
Accepted November 25, 2025
Abstract
Lead is a heavy metal that poses significant risks to human health, particularly affecting semen quality. This systematic review and meta-analysis aimed to assess the impact and associated mechanisms of lead on various semen parameters. A systematic search was conducted from March 18th to April 30th, 2024, utilizing Google Scholar, PubMed, and Scopus, and applying the PECOS model to identify pertinent studies. A total of seventeen studies fulfilled the inclusion criteria. The results of our analysis indicated that blood lead levels were markedly elevated in men exposed to lead compared to control subjects (SMD -7.06 [95% CI: -9.03, -5.08], p < 0.00001), with analogous results observed for semen lead levels (SMD -3.42 [95% CI: -5.22, -1.62], p = 0.0002). Lead exposure was linked to significant decreases in ejaculate volume (SMD 0.81 [95% CI: 0.16, 1.45], p = 0.02), sperm count (SMD 2.10 [95% CI: 1.11, 3.09], p < 0.0001), sperm concentration (SMD 0.77 [95% CI: 0.09, 1.44], p = 0.03), and total motility (SMD 2.20 [95% CI: 1.28, 3.11], p < 0.00001), as well as an increase in abnormal sperm morphology (SMD -3.29 [95% CI: -4.87, -1.71], p < 0.0001). While reductions in testosterone levels and elevations in semen malondialdehyde were noted, these changes did not reach statistical significance. These findings highlight the urgent need for strategies aimed at reducing lead exposure and emphasize the importance of further research into potential mitigating interventions.
