The aim of this study was to investigate the frequency of toxoplasmosis in male volunteers referred to Fertility and Infertility center. The percentage of anti-Toxoplasma IgG was 48%, in the current study. Most of the data on the prevalence of anti-Toxoplasma antibodies collected from female population in comparison to limited data on male population (Borráz-León, Rantala et al. 2021). A similar study in consistent with the current results by Hlaváčová et al. in the Czech Republic obtained a prevalence of 48% in terms of anti-Toxoplasma IgG however the sample size was bigger than the present job (Hlaváčová, Flegr et al. 2021). The Colossi study found toxoplasmosis frequency of 25% in infertile men (Colosi, Jalali-Zadeh et al. 2015). In another study in male blood donors in Baghdad, antibody against T.gondii was found to be 30% (Zghair, Al-Qadhi et al. 2015). The toxoplasmosisinfection rate in the female participants in Hamadan was between 25.6–30% (Maghsood, Fallah et al. 2013, Sardarian, Maghsood et al. 2019) which was lower than the present results.
The highest frequency of infection was in the age range of 36 to 40. Hlaváčová's study also showed the highest frequency in this age range (Hlaváčová, Flegr et al. 2021).
People who had fertility problems had the frequency of the 49% anti-Toxoplasma IgG. Regarding sperm count or sperm pathology, 48% with positive IgG had sperms with abnormal morphology and 48% had sperms with inappropriate movement or no movement. The frequency of toxoplasmosis had no significant relationship with the fertility rate (37%, p = 0.46). Hlaváčová reported, 96.26% of men with toxoplasmosis had sperm problems (Hlaváčová, Flegr et al. 2021). Colosi et al as well, expressed the number of T.gondii positive cases was significantly higher in the ones with urological problems (21.34%), no significant difference was observed in terms of sperm pathology in spermogram (Colosi, Jalali-Zadeh et al. 2015). In the study of Abdullah et al. in Iraq, no statistically significant difference was observed between the frequency of toxoplasmosis and sperm parameters (Ab-dulla, Abood et al. 2016).
No significant change was observed in testosterone levels while, in the study by Zouei et al, the test group with antibodies against T. gondii showed a significantly higher level of testosterone compared to the healthy group (Zouei, Shojaee et al. 2018). Apart from age, there were no other significant differences observed between toxoplasmosis and other variables.
The frequency of anti-T.gondii in this group of men who mostly referred to this center due to fertility problems was more than other studies and more than the normal male and female population. Given the restrictions on extensive sampling and the unwillingness of the volunteers to participate, a proper correlation between toxoplasmosis and infertility could not be established.
Although male infertility is nearly idiopathic, infertility in couples is a complicated, multifactorial issue. It appears that increased inflammatory cytokine levels in the male reproductive system can damage sperm in microbial infections (Azenabor, Ekun et al. 2015). T. gondii infection activates the Th1 cells to produce excessive levels of cytokines in the tissue. Conversely, studies carried out in experimental models reveal that the oxidative stress that T. gondii imposes to the male reproductive organs can interfere with sperm function. The quality of sperm is decreased after ROS production (Sanocka and Kurpisz 2004, Nazarlu, Matini et al. 2020). Additionally, male hormones are suppressed by high ROS levels (Darbandi, Darbandi et al. 2018). The amount of testosterone did not significantly change in this study, but two months after an acute infection, male mice in experimental studies had lower levels of testosterone (Taherimoghaddam, Bahmanzadeh et al. 2021). The duration of infection, the study population, and the test method all affect the relationship between testosterone hormone and toxoplasmosis (Zouei, Shojaee et al. 2018).
Toxoplasmosis can result in changes to the male reproductive system and decreased fertility in males, as multiple research studies have documented instances of the parasite affecting the reproductive organs (Arantes, Lopes et al. 2009, Lopes, Rodriguez et al. 2013, Asgari, Keshavarz Valian et al. 2015, Tong, Hlaváčová et al. 2023).
Furthermore, the likelihood of sexual transmission is increased by the high frequency of toxoplasmosis in women whose partners showed the parasitic infection (Hlaváčová, Flegr et al. 2021).
In conclusion, it seems that toxoplasmosis does not affect fertility itself, even though side factors such as the immune system and the production of pro-inflammatory substances are considered to facilitate the disruption of fertility factors in toxoplasmosis. Finally, diverse consistent results point to the accuracy of the consequence, while conflicting results highlight the need for more study in this area. For instance, a larger sample size tends to bring the frequency closer to the true prevalence.