Geographical distribution of semen quality parameters in men visiting tertiary care infertility centers across india: A retrospective study

INTRODUCTION

Failure to achieve a clinical pregnancy after at least a year of regular, unprotected intercourse is considered infertility.^[1] Recent trends suggest that male factor infertility accounts for nearly 35 to 40% of all infertility cases.^[2] The public and the scientific community are both concerned about a global drop in sperm quality as numerous research reports have repeatedly been published, either supporting or refuting a compromise in sperm quality.^[2,3,4] The pathogenesis of this decline is multifaceted, as any change to the normal physiology of the male reproductive organs may impair the spermatogenesis process, thereby giving rise to conditions such as oligozoospermia (low sperm count), asthenozoospermia (poor or loss of motility), teratozoospermia (abnormal morphology), and azoospermia (sperms absent from ejaculation).^[3,5,6]

Various retrospective studies suggest a decrease in sperm concentration in some regions of the world, mainly due to dietary preferences and lifestyle habits.^[7,8,9,10] The baseline sperm quality and functional parameters in fertile Indian men have been documented by World Health Organization (WHO),^{[11,12,13,14]} but the study examining changes in sperm attributes in Indian men over time found no appreciable drop in sperm count from 1990 to 2000.^[4] Given the large population density, diversity of the Indian population, disparities in meteorological conditions, and dietary preferences, it is important to determine whether a comparable trend is present across the many regions or zones of the same country.

Aim and objective

The objective of this study was to examine the regional variations in sperm concentration, total sperm motility, sperm morphology, and incidence of azoospermia among males in India seeking infertility evaluation over 4 years.

Material and methods

In addition to receiving signed analysis reports for their personal records, participants were required to give written consent for the inclusion of their analysis results in the study dataset. The study received approval from the Indira IVF Hospital Private Limited (IIHPL) Institutional Ethics Committee, ensuring adherence to ethical guidelines and patient confidentiality (ECR/1614/Inst/RJ/2021). Informed consent was not required in this study.

RESULTS

The findings revealed statistically significant variations in the seminal traits of the participants tested for 4 years, i.e., between 2018 and 2021. These variations were particularly pronounced in sperm density, motility, and normal sperm morphology, as determined by the WHO criteria (2010).

In the 64,452 couples that were examined, we found that 72.1% of the male partners had aberrant semen parameters. The overall and zone-wise semen parameters trend during these 4 years has been elaborated in detail in Table 2.

Infertile men had a mean sperm density of 47.5 ± 26.8 million/mL (n = 11,268) in 2018, which was much higher than the average sperm density seen in 2020 (44.22 ± 27.32 million/mL) and 2021 (43.92 ± 29.92 million/mL).

The mean sperm count (44.67 ± 28.41), sperm motility (36.87 ± 24.16), and sperm morphological defects both showed a similar pattern during these successive years. The results revealed significant variations in seminal traits, with the mean sperm count being 44.67 million/mL, sperm motility at 36.87%, and sperm morphology at 2.21%. As per WHO guidelines, 80.9% had a normal sperm count, 43.4% had normal sperm motility, and 70% of the participants had normal sperm morphology (>4%). Overall, 72.1% of the participants had abnormal semen quality parameters (either of three parameters), contributing to three fourth of male factor infertility. In comparison to WHO guidelines (2010), 9.1% of samples were reported to be having azoospermia [Table 2].

Table 2 shows the highest mean sperm count was observed in the North zone (48.88 ± 26.53), whereas the lowest was in the South zone (37.92 ± 24.78). The East zone had the lowest mean sperm motility (36.37 ± 23.16), while the West zone had the highest (37.31 ± 25.54). The East zone had the lowest mean sperm morphology (1.85 ± 1.74), whereas the North zone had the highest (2.51 ± 1.67) of azoospermia (absence of sperm in ejaculate), the overall prevalence was 9.1%. Significant variations were observed among the zones (P < 0.001). The East zone had the highest incidence of azoospermia (14.2%), while the South zone had the lowest (5.8%).

Table 3 shows the univariate analysis which revealed a significant association between age groups and the odds of the event. The odds of having abnormal sperm parameters were found to be lower in the age group “≤30” compared to the higher age group. The year-wise analysis showed that in 2021, the odds ratio is 2.415, indicating a significant increase in the odds of having abnormal sperm parameter compared to 2018 (statistically significant with P-value <0.001). The odds ratio increases with each passing year, indicating a rising trend in abnormal sperm parameters over passing year [Table 4].

DISCUSSION

This is the first study to examine the semen quality in a sizable population of Indian men from the length and breadth of the country.^[14] Our data explicitly showed that the semen quality is declining over the last 4 years. Our results corroborate earlier reports that human semen quality appears to be diminishing globally.^[1,2,15,16] To rule out bias, the protocol for semen analysis remained unchanged during the research period. Though we followed WHO 2010 guidelines for evaluating semen parameters (as the study duration was from 2018 to 2021), but we do have the opportunity to compare as per the new WHO 2021 criteria [Table 5].

It may also be noted that the reason behind the decline in semen quality may be caused by unknown environmental, dietary, socioeconomic, or other factors.^{[1,2,9,11,20]} Exogenous estrogenic chemicals can disrupt neonatal testicular development and lower adult men's sperm production when they are exposed to them in utero.^{[17,18,19,20,21,22]} Crucially, our findings are in tandem with studies that cases of oligoasthenoteratozoospermia point to a qualitative impairment of spermatogenesis with a probable impairment of the Sertoli cells.^[23]

It is important to investigate population-based trends in semen quality over time as significant geographic and ethnic variance in semen quality has been observed by various researchers.^{[9,12,24,25,26,27]} Earlier research has suggested a decline in the quality of semen in various regions of the world.^[9,10,11] The baseline sperm concentration and motility for Indian men were reported to be 68.22 ± 15.14 million/mL and 40.95 ± 9.15%, respectively.^[12] A prior study that looked at infertile men in the northern region of India for 11 years failed to show any change in the quality of their semen.^[4] The mean sperm count recorded in our study was 44.67 ± 28.41 millions/mL.^[12] The motility, however, did not significantly change between the two trials, indicating a clear reduction in sperm concentration in India. The current study contains few drawbacks. Since the study's participants were infertile patients, they may not accurately represent the general population. Additionally, there is a lack of information on factors that may affect the quality of semen, such as occupation, smoking, eating habits, and stress levels. However, a lengthier study period may be affected by a variety of circumstances, such as changes in the laboratory staff, tools, and methodology over time. India has a highly diverse human population, making up about 25% of the world's population. It is crucial to evaluate the semen quality in various regions of the nation for additional confirmation of the claim due to the variety of environmental, nutritional, socioeconomic, and climatic aspects. Further studies using a large cohort of normal subjects with additional information on their occupation, socioeconomic condition, and lifestyle-related factors are warranted to confirm the findings of the current report. The significant time-related decline in semen quality observed in this study has important implications for fertility.

A similar study from our neighboring countries like Pakistan and Nepal, found oligozoospermia to be the most common cause of infertility in males.^[27] In a study done on the African population, literature reported that cases of asthenozoospermia were the most common. In our study, we reported that sperm motility was impacted in 36.87 ± 24.16% of the cases. According to some other literature,^[28] the prevalence rate of azoospermic men was 10 to 20% which is in tandem with our observation, that is, 9.2%. However, this is now documented that even though sperm concentration or motility is good, a morphological defect may be the dominant factor reflecting the actual sperm fertilization capacity.^[30][31][32] Variations seen in the results may be due to local ethnic differences, environmental factors, dietary disparity, socioeconomic factors, and evolving lifestyle factors.

Currently, very few management strategies and therapies are available to manage or treat male infertility. New strategies to determine the underlying cause of idiopathic infertility and treatment to reverse the disorders would be the game changers in addressing male factor infertility.

CONCLUSION

Though we could not find any significant regional variation in sperm quality parameters the declining trend was well-marked over time and the prevalence of azoospermia was found alarming.