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Updated: Jun 18, 2026
06:40
Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization
Published on: October 24, 2025
What has happened to human fertility?
1Department of Epidemiology and Public Health, Imperial College, London W2 1PF, UK. m.joffe@imperial.ac.uk
Human Reproduction (Oxford, England)
|November 26, 2009
Summary
Male reproductive health is declining, with rising testicular cancer and impaired semen quality, suggesting environmental and genetic factors. This challenges current explanations and highlights unique human reproductive vulnerabilities.
Area of Science:
- Reproductive Medicine
- Environmental Health
- Genetics
Background:
- Semen quality has declined in some populations, contrasting with potential increases in couple fertility.
- Rising trends in testicular cancer and other reproductive issues suggest environmental and genetic influences.
Purpose of the Study:
- To explore hypotheses for the apparent inconsistency between declining semen quality and increasing couple fertility.
- To investigate the environmental and genetic factors contributing to male reproductive health decline.
- To propose an alternative pathogenesis for male reproductive system impairment.
Main Methods:
- Review of epidemiological trends in semen quality and testicular cancer.
- Analysis of genetic and environmental interactions in reproductive health.
- Critique of the endocrine disruption hypothesis.
- Development of an alternative pathogenesis model.
Main Results:
- Evidence points to both environmental and genetic origins for male reproductive health issues.
- Infertility inheritance poses an evolutionary paradox.
- Poor semen quality is linked to testicular cancer and zygote development, impacting offspring health.
- Human reproduction exhibits higher impairment rates than other mammals.
Conclusions:
- The endocrine disruption hypothesis inadequately explains observed epidemiological patterns.
- An alternative pathogenesis is proposed, considering specific environmental exposures.
- Understanding the evolutionary or historico-social origins of human reproductive specificity is crucial.
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