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Year : 2014  |  Volume : 3  |  Issue : 4  |  Page : 278-283

Impact of age, verified occupation and lifestyle on semen parameters of infertile males in Jaipur: A preliminary study


Department of Zoology, Centre for Advanced Studies, University of Rajasthan, Jaipur, Rajasthan, India

Date of Web Publication16-Oct-2014

Correspondence Address:
Asha Asha
Department of Zoology, Centre for Advanced Studies, University of Rajasthan, Jaipur - 302 004, Rajasthan
India
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Source of Support: The Indian Council of Medical Research, New Delhi for the fi nancial support (project No. 5/10/2/2005-RHN), Conflict of Interest: None


DOI: 10.4103/2278-344X.143075

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  Abstract 

Background: Lifestyle factors are the amendable habits and ways of life that can greatly influence overall health and well-being, including fertility. Infertility is a medico-socio problem, and a large proportion of childless people are confronted with social stigmatization and personal frustration. It has become more socially acceptable to delay fatherhood, but the heritable consequences of this trend remain poorly understood. Advancing paternal age, occupation and lifestyle has been implicated in a broad range of abnormal reproductive and genetic outcomes. Objective: The study presents a preliminary datum about the relationship of age, occupation and verified lifestyle on semen parameters in infertile males of Jaipur (Rajasthan). Materials and Methods: Clinical examination, history of infertility, age, occupation, lifestyle, etc., of 102 infertile subjects were recorded predesigned performa. Results: Based on age subjects were divided into two groups. The respective age of infertile subjects in groups I and II ranged 19-30 years and 31-45 years. A significant (P < 0.05) decline was observed in sperm motility and vitality above the age of 30 years (group II) as compared to below than 30 years (group I) of age. A significant inverse (r = −0.25, −0.20, P < 0.05) correlation were found between sperm motility and vitality to age of group II. In group I, conversely, these parameters was found to be positively correlated with age. Highest prevalence of azoospermia occurs in farmers (66.66%, 50%) in groups I and II. The least azoospermia was found among casual laborers in both high and low age groups. In group, I highest percentage of azoospermia (55.55%) subject were alcoholic, and smoker (50%) and 50% severe oligozoospermia subjects were smokers in both the groups. Conclusion: The age is intimately related to decreasing in sperm motility and vitality, whereas, least effect is observed on sperm count. Occupationally, the highest prevalence of abnormal semen quality is noticed in farmers. Lifestyle of alcohol consumption and smoking further diminishes the semen quality. Our findings may have important implications for men who choose to delay fatherhood and occupationally exposure to solvents and alcoholics.

Keywords: Age, infertility, lifestyle, occupation, semen analysis


How to cite this article:
Asha A. Impact of age, verified occupation and lifestyle on semen parameters of infertile males in Jaipur: A preliminary study. Int J Health Allied Sci 2014;3:278-83

How to cite this URL:
Asha A. Impact of age, verified occupation and lifestyle on semen parameters of infertile males in Jaipur: A preliminary study. Int J Health Allied Sci [serial online] 2014 [cited 2019 Sep 20];3:278-83. Available from: http://www.ijhas.in/text.asp?2014/3/4/278/143075


  Introduction Top


Lifestyle factors, including age when starting a family, nutrition, weight management, exercise, psychological stress, cigarette smoking, recreational and prescription drugs use, alcohol and caffeine consumption, environmental and occupational exposures, preventative care, and other behaviors are modifiable and may impact fertility. [1] Fertility has become an important issue in public health, As more couples are choosing to delay childbearing, it is becoming increasingly important to understand how male age affects the infertility. Some rodent and human studies have reported that certain aspects of semen quality decline with age. [2],[3],[4] However, most human studies have been conducted in clinical settings with sperm donors or men with fertility concerns. Moreover, few of the clinical studies included men over the age of 50 years and seldom considered potential confounders that might explain changes with age, such as smoking history or occupational exposures. [2] Age-related changes are known to occur in the testis where alternations have been noticed in basal membranes, seminiferous tubules and tunica albuginea. The Leydig cells decrease in a number and accumulate the "ageing" pigment lipofuscin. [5],[6],[7]] Age causes localized changes in spermatogenesis, which include a reduction in dark type and intratubular clustering of pale type spermatogonia A. Spermatogenesis arrested at the spermatocyte I stage and numerous malformation in spermatids have been noticed. [8] The relationship between age and semen quality and lifestyle impacts on infertility in Indian prospective is scare and in the context to Jaipur, has not yet been carried out. Taking consideration of above, the aim of the current study is to document the semen parameters of infertile subjects in relationship with age, occupation and lifestyle.


  Materials and methods Top


The study population comprised from couples who presented themselves for various infertility problems at the Division of Infertility, Department of Urology, SMS Hospital, Jaipur, India, during October 2007-2010. Five hundred infertile couples were selected for initial screening. After exclusion of infertility through female factors, aspermic and subjects with erectile dysfunction and obstructive azoospermic, 102 infertile subjects were recruited for the present investigation. The details of occupation, status of infertility, viz., primary/secondary, details of previous ailments/treatment, lifestyle, occupation, information on age, health problems, etc., were recorded. A complete urogenital examination of each subject was recorded in a predesigned performa. The study was approved by the Institute Ethical Committee and a written consent to participate in the study was obtained from each subject.

All subjects were allocated into following two groups:

  • Group I (low age): Infertile subjects (n = 71) with 18-30 years of age
  • Group II (high age): Infertile subjects (n = 31) with 31-45 years.


Semen samples were collected by masturbation into a clean sterile sample collection vial, under aseptic conditions. Subjects were instructed to abstain for at least 48 h prior to collection the semen sample. The samples were liquefied for at least 20 min in a water bath at 37°C, but no longer than 1 h prior to performing a routine semen analysis. Semen analysis was performed within 1 h after collection of semen. Semen liquifaction, color, pH, appearance, consistency, agglutination, semen volume, sperm count, motility, vitality and sperm morphology was carried out. [9]

Statistical analysis

Values are represented as mean ± standard deviation. One-way analysis of variance was employed for statistical comparison. The difference between means was analyzed by Holm-Sidak multiple comparison test to detect the inter-group difference by using the statistical software SPSS version 11.5 (SPSS Inc., Chicago, IL, USA). A P < 0.05 were considered as significant. Relationship between two variables was determined by Karl Pearson's coefficient of correlation.


  Results Top


Out of 102 infertile subjects 69.61% were aged 19-30 years in the group I and 30.39% aged 31-45 years were in group II [Table 1]. Out of 102 subjects only 3 (2.94%) subjects were found with the case of secondary infertility in group II, rest of the subjects were the case of primary infertility.
Table 1: Age and seminal characteristics of infertile subjects

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The subjects were broadly categorized as (i) businessmen, (ii) professionals, which include officials of governmental, semi-governmental and private organizations, (iii) casual laborers, (iv) farmers, (v) occupational heat/chemical exposure, and (vi) others (unspecified jobs). Semen findings according to occupations showed that the highest prevalence of azoospermia occurs in farmers ((6) 66.66%, (5) 50%) in groups I and II. Next prevalent category after farmers was heat/chemical exposure ((5) 45.45%) and businessmen ((5) 35.71%) in group I. The least azoospermia were found among casual laborers in both high and low age groups. After azoospermia next prevalent abnormalities was severe oligozoospermia found in professionals ((9) 37.50%, 20% (2)) and casual laborer (33.33%, [3] 33.33% (2)) in groups I and II [Table 2]. Based on the subjects profile, the lifestyle habits were broadly classified into three categories, viz., (i) daily excessive consumption of alcohol, (ii) excessive cigarette smoking and (iii) tobacco chewing. Out of 102, 65 (63.72%) subjects are under these categories. The highest percentages of azoospermia subjects were alcoholics (55.55%) in the group I and with a habit of tobacco chewing (46.66%) in group II. In both groups I and II, 50% of the subjects were severe oligozoospermia with a habit of cigarette smoking and (24%, 20%) subjects were tobacco chewers [Table 3]. Abstinence period in groups I and II respectively was ranged from 0 to 6 (3.36 ± 0.31) and 0 to 5 (4.96 ± 1.04) days. Semen liquefaction, color and consistency were normal in all semen samples. Semen pH, volume was nonsignificantly different in high age group (group II) as compared to low age group (group I) [Table 1]. All semen samples were free from agglutination.
Table 2: Semen findings according to occupation

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Table 3: Semen findings according to lifestyle

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Out of the total 102 subjects, 34 (33.33%) subjects were recorded azoospermia that indicates that azoospermia accounted for the majority of infertility cases. In group I, 25.35% (18) subjects were normozoospermia, 12.67% [9] oligozoospermia, 26.76% [10] severe oligozoospermia and 35.21% [11] were azoospermia. In group II the respective subjects for normozoospermic, oligozoospermic, severe oligozoospermic and azoospermic were 22.58%, [7] 29.03%, [9] 19.35% [6] and 29.03% [9] [Table 4]. A nonsignificant difference in sperm count was observed in group II when compared to group I [Table 1]. The mean of sperm motility in groups I and II were 35.45 ± 4.28, 25.45 ± 5.61. In groups I and II, 60.56% (43) and 74.19% (23) subjects, respectively, had < 50% sperm motility. Sperm motility was significantly (P < 0.05) decreased in group II (high age group) when compared with group I (low age group). Sperm motility was found to be inversely and significantly (r = –0.25, P < 0.05) correlated to age of group II, whereas, in group I sperm motility was nonsignificantly and positively correlated (r = 0.15) with age [Figure 1]a and b.
Figure 1: (a and b) The relationship between age (years) and sperm motility (%) in groups I (a) and II (b). Individual data points are shown and relationship between variables indicated by linear regression lines. Note a nonsignificant and positive correlation in group I (a) and a significant (P < 0.05) and inversely correlation in group II (b)

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Table 4: Prevalence of abnormal semen parameter

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Sperm vitality of groups I and II were 43.40 ± 4.20% and 33.64 ± 5.73%, respectively. Sperm vitality was significantly (P < 0.05) less in group II (high age group) as compared with group I (low age group) [Table 1]. Sperm vitality (r=-0.20, P < 0.05) was significantly and inversely correlated with age of group II, whereas, in groups I sperm vitality was nonsignificantly and positively correlated (r = 0.14, P > 0.05) with age of subjects [Figure 2]a and b. The normal sperm morphology in groups I and II respectively, was 29.75 ± 3.57%, 27.09 ± 5.47%. Normal sperm morphology of group II (higher age group) was nonsignificantly decreased when compared with group I (low age groups) [Table 1].
Figure 2: (a and b) The relationship between age (years) and sperm vitality (%) in groups I (a) and II (b). Individual data points are shown and relationship between variables indicated by linear regression lines. Note a nonsignificant and positive correlation in group I (a) and a significant (P < 0.05) and inversely correlation in group II (b)

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  Discussion Top


The analysis of semen samples, in the present study, reveals the prevalence of the maximum number of azoospermia subjects in both the low and high age groups of infertile subjects. Studies conducted in Indian prospective have reported 57% [12] and 19% [13] incidences of azoospermia. The prevalence of azoospermia and oligozoospermia in the metropolitan cities of Mumbai, Bengaluru and Jalandhar, were similar to those reported in most other parts of the world. [14],[15] A study conducted by Mehta et al. [16] has documented that prevalences of azoospermia in Kurnool and Jodhpur, respectively, was 38.2% and 37.3%. In this respect, the presence of 33.33% of azoospermia in Jaipur was within the range, as reported in Indian perspectives, but higher than those reported from other part of the world. [10],[14],[15],[17],[18],[19],[20]

Environmental factors such as heat, chemical and lifestyle including diet, smoking and alcohol are known to have adverse effects on semen parameters. [21],[22] Now a days societal way of life like smoking, alcohol drinking, tobacco chewing and other factors like tight clothing, long driving (increase the scrotal temperature) affects the sperm quality. Lifestyle like smoking, alcohol drinking, tight clothing or long driving, etc., now a days becoming more responsible for detrimental effects on semen profiles. Alcohol use in males can affect spermatogenesis and/or sperm physiology and may even cause impotence. It is reported that 75% of children with fetal alcohol syndrome have fathers who were alcoholics. [23] The present study shows that maximum subjects that is, 55.55% subjects in group I were azoospermia had a habit of alcohol consumption. Our study indicates that the majority of subjects having a habit of alcohol consumption belong to the low age group. The next prevalent category, in the present study, were smokers, 50% subjects in group I and 40% in group II had a smoking habit. In group II 46.66% and group I 40% subjects had a habit of tobacco chewing are the case of azoospermia. In severe oligozoospermia cases, 50% subjects of groups I and II were smokers. Male smokers had shown decrement in sperm count, impaired sperm motility, more abnormal sperm and reduced testosterone levels; they can potentially contribute to congenital abnormalities and asthma in their children. Heavy paternal smoking may increase the risk of childhood cancer in the offspring. [24] According to Ramlau-Hansen et al. [25] heavy smokers had 19% lower sperm counts than nonsmokers. In a study, Gaur et al. [11] showed that motility is one of the first sperm parameters affected, and asthenozoospermia may be an early indicator of reduced semen quality in light smokers.

Men working in the agriculture sector are at more than 10 fold increased risk of infertility in comparison to those in other occupations. [26] There is a serious concern about the effects of pesticides in the male parent on reproduction and the health of children born to him. In our finding, a higher percentage of semen abnormalities were noticed in farmers (azoospermia and severe oligozoospermia), heat/chemical exposure and businessmen (azoospermia) than other occupational groups. High percentage of azoospermia in farmers may be explained by due to exposure of pesticide or other organic solvents. The low sperm count in businessmen could be explained by their lifestyle and social involvement that may interfere with semen quality. This indicates that lifestyle of young ones severely affects their semen quality.

Our findings indicate that age, occupation and social lifestyle has a detrimental effect on semen parameters. Our findings clearly evidenced on age-dependent reduction in semen quality of infertile subjects. Similar results have also been reported by Ford and associates [27] that age of male has been associated with a decline in semen quality. Who concluded that, men above 35 years had half the chances of fathering a child within 12 months compared with men aged <25 years, after controlling for women's age and other factors.

Increased age in infertile men is associated with the decline in sperm vitality whereas, motility and morphology does not show a significantly affected. [28] However, our study, revealed a significant decline in total percentage of motility and vitality in age group II as compared to group I. Sperm motility and vitality were also found to be significantly and inversely correlated to age of group II. Sperm morphology does not reveal any significant difference in both the groups, which is a concord finding of Brahem et al. [28] Increased paternal age should be associated with unsuccessful or abnormal pregnancy as a consequence of fertilization with damaged spermatozoa. [29]

Girsh et al. [30] also suggested that sperm function is an age dependent factor and could be a reason for failure in in vitro fertilization cycles. In contrast to above observation, Winkle et al. [31] found that seminal parameters and sperm DNA fragmentation did not reveal a significant change with the increasing male age. However, we noticed an evidence of significant age-dependent reductions in semen quality which are in agreement with earlier findings. [32],[33],[34],[35] The highest effect of age was observed on sperm motility and vitality, and intermediate effects were noticed on sperm morphology and the least effect on sperm count. Our finding further supports earlier reports for semen quality of infertile patients and sperm donors. [2]

In conclusion, our study indicates a significant correlation between age, occupation, lifestyle and semen quality, most notably on sperm motility and vitality and the least effect on sperm count. Absolutely normal sperm parameters were observed at age ≥ 20-30 years while the most significant reduction in sperm parameters occurred after the age of 35 years. Occupationally farmers, heat/chemical exposure and businessmen having habits like alcoholics and smokers had the highest prevalence of abnormal semen quality. Thus, our findings may have important implications for men who choose to delay fatherhood and occupationally exposure to solvents and alcoholics.

 
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    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]


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