A retrospective analysis of semen samples and reproductive hormones in Africa and the middle east

Abstract

Semen analysis is the cornerstone for the investigation of male infertility. Semen quality can be influenced by geographical location, age, ejaculatory abstinence, and season. In 2010, the WHO published criteria for human semen characteristics that were markedly lower than those previously reported. Many reports have discussed the methodology used by the WHO to set the 2010 reference values. Some of the limitations of the WHO (2010) study included an undefined ejaculatory abstinence period, the limited representation of different age groups, and a limitation in geographical representation as the study did not include any data from Africa and Middle East. Therefore, the current cohort study was designed to provide retrospective data on semen quality (Africa and Middle East) and reproductive hormones (Middle East) in patients who underwent semen analysis and endocrine investigation at Andrology Laboratories in South Africa and Qatar. The effects of geographical location, age, ejaculatory abstinence and seasonal changes were evaluated. Furthermore, data from Africa (from the current cohort study) was compared to data from America, Asia, Australia and Europe obtained from global data from Cooper et al. (2010) and Campbell et al. (2021). Semen analysis reports (n = 70,765) for Africa and Middle East were obtained from Ampath Andrology Laboratory (n = 35,516), Lancet Andrology Laboratory (n = 24 967), Androcryos Andrology Laboratory (n = 7 450) and Hamad Medical Center (n = 2,832). Basic semen parameters such as semen volume, sperm concentration, total sperm count, progressive motility, total progressively motile count, sperm morphology, total normal sperm count, and functional sperm count such as DNA fragmentation, sperm viability and oxidation-reduction potential (ORP) were collected for the purpose of the study. Furthermore, reproductive hormones (estradiol, follicle stimulating hormone, luteinizing hormone, prolactin and testosterone), as well as seminal epithelial and red blood cells were investigated. All statistical analysis was done using the MedCalc® statistical software 19.5 with P-value of < 0.05 considered statistically significant. Men residing in Africa and Middle East had median ejaculate volume, sperm concentration, total sperm count, progressive motility and normal morphology within the normal thresholds recommended by WHO (2010). A prevalence of 20.3% for oligozoospermia and 3.6% for azoospermia were found in men residing in Africa and the Middle East. Men residing in the MENA region had sperm vitality below the recommended threshold and a median SDF higher than current recommended thresholds. Compared to Southern and Eastern Africa, the MENA region had generally worse semen parameters, most notably in the Middle East region. In Southern Africa, the highest semen parameters were found in men residing in Mozambique and Zimbabwe while the lowest were observed in patients residing in Zambia. In South Africa, the Free-State and Mpumalanga provinces had the lowest median sperm concentration. Age was found to negatively influence semen parameters in Africa and the Middle East. In the MENA region, an age-related decline in testosterone and prolactin, and increase in FSH was found, with no significant changes for LH and estradiol with age. The duration of abstinence had a statistically significant positive influence on semen volume, sperm concentration and progressive motility, while SDF worsened with the increased duration of abstinence. Furthermore, the results show a temporal decline in semen parameters between 2005 and 2019 among men from sub-Sahara Africa. A seasonal change in semen parameters of men residing in sub-Sahara Africa below the equator was found, with sperm concentration and total sperm count higher in winter compared to summer and autumn. The lowest sperm concentration was found in summer. Lastly, the results indicated a reduced semen quality in men residing in Africa compared to those living in America, Asia, Australia and Europe when comparing to global data from Cooper et al. (2010) and Campbell et al. (2021). The differences observed in semen quality and hormones in this study may indicate different environmental exposures and lifestyle changes in the investigated regions which requires further investigation.