Indian Journal of Pathology and Microbiology

: 2010  |  Volume : 53  |  Issue : 1  |  Page : 35--40

Alcohol intake and cigarette smoking: Impact of two major lifestyle factors on male fertility

Dushyant Singh Gaur, Manju S Talekar, Ved Prakash Pathak 
 Department of Pathology, Himalayan Institute of Medical Sciences, Jolly Grant, Dehradun - 248 140, Uttarakhand, India

Correspondence Address:
Dushyant Singh Gaur
Professor of Pathology & In-charge Andrology Laboratory, Himalayan Institute of Medical Sciences, Dehradun - 248 140, Uttarakhand


Context: Lifestyle factors, like alcohol intake and cigarette smoking, have been reported to affect male fertility. Aims: To find out the specific impact of alcohol and smoking on semen quality of male partners of couples seeking treatment for primary infertility. Materials and Methods: From the semen samples analyzed in our andrology laboratory, results of 100 alcoholics and 100 cigarette smoker males were studied following WHO guidelines and compared with 100 strict nonalcoholic and nonsmoker males for presence of asthenozoospermia, oligozoospermia and teratozoospermia. Statistical Analysis: Data was analyzed by F- test using Microsoft Office Excel 2003. Results: Only 12% alcoholics and six per cent smokers showed normozoospermia compared to 37 % nonalcoholic nonsmoker males. Teratozoospermia, followed by oligozoospermia dominated alcoholics. Overall impact of asthenozoospermia and teratozoospermia, but not of oligozoospermia, was observed in smokers. Light smokers predominantly showed asthenozoospermia. Heavy alcoholics and smokers showed asthenozoospermia, teratozoospermia as well as oligozoospermia. Conclusions: Asthenozoospermia, the most common semen variable in our study, can be an early indicator of reduction in quality of semen. Alcohol abuse apparently targets sperm morphology and sperm production. Smoke-induced toxins primarily hamper sperm motility and seminal fluid quality. Progressive deterioration in semen quality is related to increasing quantity of alcohol intake and cigarettes smoked.

How to cite this article:
Gaur DS, Talekar MS, Pathak V. Alcohol intake and cigarette smoking: Impact of two major lifestyle factors on male fertility.Indian J Pathol Microbiol 2010;53:35-40

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Gaur DS, Talekar MS, Pathak V. Alcohol intake and cigarette smoking: Impact of two major lifestyle factors on male fertility. Indian J Pathol Microbiol [serial online] 2010 [cited 2021 Dec 4 ];53:35-40
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Infertility is a disease of the reproductive system that impairs the body's ability to perform the basic function of reproduction. Infertility, defined as the inability to conceive after 12 months of unprotected intercourse, affects 10-15% of all couples. [1]

Facing infertility can be very difficult for both men and women: it is emotionally stressful and physically taxing on most couples. Male infertility plays a key role in conception difficulties of up to 40% infertile couples. Although in some men a specific disorder may be present, in majority no apparent reason for infertility could be found. This has drawn attention to the impact of lifestyle and environmental factors, especially diet, obesity, smoking, alcohol intake, recreational drug use, and exposure to environmental toxins, on reproductive health of such men. [2]

Cigarette smoking and alcohol intake, both largely avoidable, are two such lifestyle factors observed to have a negative impact on male fertility. [2],[3],[4],[5],[6] This study aims to evaluate the impact of these factors on specific aspects of sperm quality of male partners of infertile couples.

 Material and Methods

This prospective study was conducted at the andrology laboratory of our pathology department. The subjects included in the study were male partners of infertile couples seeking treatment for primary Infertility at our Institute.

Selection Criteria

Since we aimed to study the impact of alcohol and cigarette smoking on specific aspects of sperm characteristics, very stringent case selection criteria were laid down. Male partner of couple facing primary infertility, married for more than one year and not using any contraceptive measures, was selected for the study.

This stringent selection was done to exclude as many known co-existing factors as possible, from the study groups and avoid the synergistic effect of alcohol and smoking on semen quality. For the same reason, healthy fertile males were not taken as controls, to nullify any undiscovered factors present, which might not be present in infertile males.

The following males were excluded from the study groups:

Those suffering from azoospermia or secondary infertility;Ex-smokers and ex-alcoholics, or those with history of tobacco/betel nut chewing, 'bidi' smoking, or substance abuse;Those with history of prolonged medication, intake of indigenous medications/herbal preparations/tonics, occupational exposure to chemicals; or excessive heat;Those with history of injury to testes , varicocele, hydrocele, undescended testis or its corrective surgery, Vasectomy-reversal surgery, history of any chronic illness like tuberculosis, mumps, etc. or pyospermia, haemospermia or chronic urinary tract infection;Those with negative semen fructose test;Males above 45 years of age. The three study groups, each comprising of 100 males, were:

Group A : Strict non-alcohol consumer and non-smokers who acted as controls.

Group B : Alcohol users but strict non-smokers were divided into three subgroups according to the average daily alcohol consumption:

Mild: those consuming 40g or less;Moderate: consuming 40-80g; andHeavy: consuming more than 80g per day. [6] Group C: Smokers, who were strict non-alcohol-consumers, were sub-grouped based on the number of cigarettes smoked per day, into:

Light Smokers: 01-20 cigarettes/day;Moderate Smokers: 21-40 cigarettes/day; andHeavy Smokers: 41 and more cigarettes/day. [7] Informed consent was taken, as a routine, from all the cases.

Sample Collection

Following strict abstinence of four to six days, samples were collected in wide-mouthed sterile containers, by masturbation, in the laboratory. Samples with partial spillage were rejected. [8] Only one sample per patient was included in the study. All samples were kept at 37 plus/minus two degrees Centigrade (37 o ± 2 o C) temperature and processed immediately after complete liquefaction.

All semen samples were analyzed for 10 primary semen parameters:

Liquefaction time, ii) Volume, iii) Viscosity, iv) Amorphous particulate matter, v) Agglutination, vi) Motility, vii) Viability, viii) Sperm density, ix) Morphology (normal forms) and x) Headless spermatozoa; as per the recommended guidelines according to the WHO manual. [9] These parameters, when taken together, indicated the presence or absence of the three main semen variables: asthenozoospermia (A), teratozoospermia (T) and oligozoospermia (O), which acted as pointers to specific need for further evaluation of their infertility.

Samples showing asthenozoospermia were those which had less than 25% spermatozoa showing linear forward progression; samples of oligozoospermia had less than 20 million spermatozoa/ml of ejaculate; and samples of teratozoospermia showed more than 70% of morphologically abnormal spermatozoa. [8],[9]

These three variables were present either individually or in various combinations such as asthenozoospermia and teratozoospermia (A+T), asthenozoospermia and oligozoospermia (A+O), oligozoospermia and teratozoospermia (O+T), and asthenozoospermia with oligozoospermia and teratozoospermia (A+O+T). Samples with normozoospermia (N) were those which had all the parameters within the recommended ranges and were thus categorized separately. [8],[9],[10]


Semen samples were examined for sperm density, sperm motility, sperm vitality, sperm morphology, presence of agglutination and particulate matter. Sperm morphology was studied on Papanicolaou stained smears , counting a minimum of 200 spermatozoa using oil-immersion lens (100´ magnification) . Sperm vitality was assessed in wet mount smears after supravital staining with aqueous eosin. [10]


The data was analyzed by F-test using Microsoft Office Excel 2003. A P-value less than 0.05 was considered statistically significant, values lesser than 0.0001 were considered highly statistically significant.


Cases were selected for the three study groups from male partners of infertile couples who presented for semen sample analysis in our andrology lab from January 2000 to December 2005. Group A comprised of strict non-alcoholic and non-smoker controls (n is equal to 100); Group B of alcohol consumers (n is equal to 100) comprised of mild alcoholics (n is equal to 40), moderate and heavy alcoholics, all of whom were never-smokers. Group C of Smokers included light smokers (n is equal to 49), moderate and heavy smokers, who had never consumed alcohol [Table 1]. Their other characteristics were as per the stringent selection criteria of the study.

To determine the contribution of each of the three main semen variables, viz. asthenozoospermia (A), oligozoospermia (O) and teratozoospermia (T), the controls (Group A) alcoholics (Group B) and smokers (Group C), were distributed according to the presence of individual semen variables or their various combinations, as observed during semen analysis [Table 2],[Table 3],[Table 4].

Group A: Controls

It was observed that among controls, normozoospermia was present in 37 cases [Table 2]. Amongst the remaining controls, though all the three main semen variables were observed, asthenozoospermia was seen in more cases in comparison to oligo- and teratozoospermia [Table 2] and [Table 4]. Thus it was inferred that even amongst otherwise healthy non-alcoholic and non-smoker controls, defects of sperm motility, count and/or morphology were present, but within permissible range; and asthenozoospermia was the most common anomaly of semen. [8].[9]

Group B: Alcohol Consumers

Only 12 cases of alcoholics showed normozoospermia, of which nine were mild alcoholics. No heavy alcoholics showed normozoospermia. Teratozoospermia (T) and oligozoospermia (O) was seen in much higher number of cases, individually or in various combinations like (O+T), (O+A+T) and (A+T), amongst alcoholics in comparison to controls. Within the three alcoholic subgroups, a progressive increase in number of cases was noticed from mild to moderate to heavy alcoholics in the categories (T), (O), (A+T) and (O+A+T) [Table 2]. However, on statistical analysis, p-value was found to be definitively significant (less than 0.05) for pure teratozoospermic (T) subgroup of alcoholics in comparison to controls [Table 2].

Overall, within the alcoholic subgroups, teratozoospermia (n = 59) dominated the semen variables and was present in 72% heavy alcoholics and 63% moderate alcoholics. Similarly oligozoospermia (n = 51) was present in as high as 64% of heavy alcoholics. Thus heavy alcoholics showed a very high percentage of defects of sperm count, morphology as well as motility [Table 4]. Statistically, P-value of teratozoospermia and oligozoospermia was significant amongst alcoholics, in comparison to controls [Table 4].

Thus alcohol appeared to contribute mostly towards developmental defects of sperm morphology and sperm production (reduced sperm count), which rose steadily, with the increasing quantity of alcohol consumption.

Group C: Cigarette Smokers

Amongst smokers, only six samples had semen parameters consistent with normozoospermia [Table 3]. In smokers, the most dominant semen variable was asthenozoospermia (A), individually (n = 24) or in combination with other variables. Thirty nine percent light smokers showed isolated asthenozoospermia; while amongst controls, isolated asthenozoospermia (A) was seen in only nine percent cases. By contrast, heavy smokers (24%) and moderate smokers (23%) had more samples with astheno - oligo-teratozoospermia (A+O+T) than light smokers [Table 3]. Statistical analysis showed that the incidence of both isolated asthenozoospermia (A), and asthenozoospermia with teratozoospermia (A+T) amongst smokers was statistically significant (p-value less than 0.05), in comparison to controls [Table 3].

Amongst smokers, overall asthenozoospermia (n = 74) dominated over other semen variables, teratozoospermia and oligozoospermia [Table 4]. Asthenozoospermia was steadily present in all sub-groups. A progressive rise in defects of sperm count as well as morphology were seen from light to moderate to heavy smokers, which showed a very high percentage of terato- and oligozoospermia [Table 4]. Statistically, the impact of asthenozoospermia (A) and teratozoospermia (T), but not of oligozoospermia (O), was significant in smokers (P-value less than 0.05) [Table 4].

Cigarette smoke appeared to contribute significantly towards impairment of sperm motility. Also, asthenozoospermia appeared to be the 'earliest' defect of sperm quality, as seen by its dominance over other defects amongst light smokers. Moreover, a steady rise was seen in defects of sperm morphology too, as the level of daily smoking increased from light to heavy smokers.


Of the myriad of factors that have been blamed for influencing the semen quality of an individual, lifestyle factors like smoking and alcohol consumption have attracted much attention in recent times, all over the world. [3],[4],[5],[6],[7],[11]

Study of semen parameters like sperm motility, sperm count and sperm morphology have conventionally been used to assess the semen quality of an individual. Of these, Sperm morphology can be the most informative semen parameter in differentiating between fertile and infertile semen samples. However, none of these measures, alone or in combination, can be considered diagnostic of infertility. [11] In our study we tried to find out the frequency with which the three main semen variables, asthenozoospermia (A), teratozoospermia (T) and oligozoospermia (O) appeared in the semen samples of alcoholics and cigarette smokers, in comparison to controls.

Alcohol Consumers

Alcohol abuse in men has been reported to cause impaired testosterone production, and atrophy of testes, which can result in impotence, infertility and reduced male secondary sexual characteristics. [11],[12],[13] However, dose-dependent effects of alcohol on human spermatogenesis are not well established. [6] Of the 100 alcoholics included in our study, only 12 alcoholics showed normozoospermia of which nine were mild alcoholics and three were moderate alcoholics, while none of the heavy alcoholics showed normal semen parameters [Table 2]. Thus alcohol consumption did reduce the number of normozoospermic cases amongst alcoholics. Of the three semen variables, teratozoospermia, oligozoospermia and their combined presence (O+T), amongst alcoholics was double or more than that found in controls, while asthenozoospermia was less frequent amongst alcoholics [Table 2]. This indicated that sperm motility defects were less frequent amongst Alcoholics in comparison to defects of sperm morphology and sperm count [Table 2]. A positive correlation with daily alcohol intake was observed amongst alcoholics, with percentage of cases increasing from mild to heavy alcoholic sub-groups for all the three variables, A, T and O [Table 2]. These observations were in agreement with few other studies. [5],[6],[11],[12] The category (A+O+T) again showed higher number of cases (n=20) amongst alcoholics than in controls (n = 11) [Table 2].

Overall, the number of cases with teratozoospermia (n = 59) amongst alcoholics was much higher than of controls (n = 34), indicating that it was the most frequently encountered sperm defect amongst alcoholics [Table 4]. Teratozoospermia was observed in 72% heavy alcoholics and 63% moderate alcoholics. Oligozoospermia, also showed much higher number of cases amongst alcoholics (n = 51) than controls, indicated progressive damage to testes in direct relation to increasing daily alcohol intake, (64% in heavy alcoholics) [Table 4]. Both teratozoospermia and oligozoospermia were statistically significant amongst alcoholics [Table 4].

Alcohol has been shown to have a deleterious effect at all levels of male reproductive system. Alcohol interferes in the feedback mechanisms of hypothalamus-pituitary-gonadal (HPG) axis resulting in impairment of production and secretion of adequate quantity or potency, of leutinizing hormone (LH) and follicle-stimulating hormone (FSH) leading to deterioration of sertoli cells. [15] Alcohol affects the leydig cells and reduces blood levels of testosterone, by reducing its production and increasing its metabolic clearance. [13] Alcohol also influences the sertoli cell functions, probably by producing damage to some of the proteins required for sperm cell production that the Sertoli cells provide. [14] Thus, alcohol induced reduction in levels of testosterone, LH and FSH not only hampers their normal morphological development and maturation of spermatozoa (producing significant teratozoospermia), it also slows down the sperm production by testicular germ cells (oligozoospermia), especially in heavy alcoholics. [15]

Other studies have reported partial to complete spermatogenic arrest amongst moderate to heavy alcohol consumers, even leading to "sertoli cell only" syndrome in advanced cases, indicating severe testicular damage. [6],[16] Progressive damage to testes and reduction of sex hormones leads to loss of secondary sexual characteristics and development of impotence and infertility. [15]

In our study, asthenozoospermia, by comparison, did not show a very strong correlation amongst mild alcoholics, but appeared in moderate and heavy alcoholics, probably as an additive feature linked to severe oligo-teratozoospermia.

 Cigarette Smokers

Smoking is a lifestyle hazard for both active and passive smokers. Although much is known now about the carcinogens in tobacco cigarette smoke and their resultant effect on organs like lungs and urinary bladder, their effects on fertility status have been less documented.

In our study, only six smokers qualified as being normozoospermic [Table 3]. This underscored the fact that smoking certainly had a definite influence on the semen quality, as concluded in several other studies. [17],[18],[19],[20] Asthenozoospermia was the most dominant semen variable contributing to the semen quality of smokers (n is equal to four) as well as Controls (n = 37), individually as well as in combination with other variables like teratozoospermia (A+T) and oligozoospermia, (A+O) and (A+O+T) [Table 3] and [Table 4]. So asthenozoospermia appeared to be a 'premier' factor contributing to the infertile status of a male. [20] However viable and morphologically normal spermatozoa may be, if they are not actively motile, showing linear forward motion in the seminal fluid, they will fail to fulfill their prime function of traversing the complex route through female genital tract, to seek and fertilize an ovum. Tragically, however, while assessing the semen quality of an individual, emphasis has always been laid on the sperm count and sperm morphology. [3],[4]

Isolated asthenozoospermia was seen in 39% light smokers and 19.2% moderate smokers while no such case was detected amongst heavy smokers [Table 2]. Since in light smokers, even this 'mild' smoking could produce reduction in the sperm motility in 39% cases, it appeared that there is no "safe" quantity of cigarette smoking that may not affect the semen quality. In 22% light smokers, teratozoospermia was observed in addition to asthenozoospermia. Thus, teratozoospermia appeared to be the next anomaly to develop in the spermatozoa of light smokers, after asthenozoospermia, further reducing the sperm quality [Table 2]. By comparison, fewer cases showed contribution of oligozoospermia amongst smokers; still their number was higher than controls [Table 3] and [Table 4].

In heavy and moderate smokers, presence of all the three variables, astheno-, oligo- as well as teratozoospermia, indicated that heavy smoking apparently had a significant contribution in the development of morphological abnormalities and reduced sperm counts besides motility defects [Table 3] and [Table 4]. [17],[18] A study on voluntary males of reproductive age showed that after ejaculation, sperm motility deteriorated much more rapidly in heavy smokers in comparison to controls. [20]

Researchers have variously concluded that toxins in cigarette smoke reach male reproductive system and their effects, though still under research, are mainly due to their direct interaction with seminal fluid components and the accessory glands, that contribute their secretions to the seminal fluid, leading to its increased viscosity, reduced seminal volume and delayed liquefaction time, hence reducing forward linear progression of spermatozoa, manifesting as asthenozoospermia. [3],[4],[17],[18],[19] In studies conducted on fertile men, it was observed that fertile men who were smokers showed reduction in semen volume in comparison to nonsmokers; and this reduction in semen volume was in proportion to the number of cigarettes smoked. [21],[22] Also, direct exposure of spermatozoa to the toxins in cigarettes smoke probably tilts the delicate balance of reactive oxygen species (ROS) that are produced by spermatozoa for their special functions like decapitation etc. Increased quantities of ROS have been shown to be detrimental to the DNA of spermatozoa, thus producing negative effect on the viability and morphology of spermatozoa. [23] Our observations were in agreement with these findings.

Smoking plays a role in producing asthenozoospermia, in otherwise normal and viable spermatozoa, which can be a very subtle 'early indicator' of deterioration in semen quality. Since 37% controls too showed asthenozoospermia [Table 4], many of these controls might be innocent 'passive smokers' or getting affected by environmental pollutants, chemicals and other unknown factors awaiting discovery. [17],[24] A higher level research of such non-Smokers may unmask the influence of these additional factors.

By contrast, oligozoospermia may also result from other etiological factors, like chronic inflammatory or infective processes, which needs further exploration. Statistical analysis of the results also underscored a significant impact of asthenozoospermia and teratozoospermia on the semen quality of smokers, in comparison to controls.

Our study could highlight that in early stages, alcohol and cigarette smoke constituents target different aspects of sperm quality; alcohol targeting sperm morphology and spermatogenesis while smoking impaired active motility of spermatozoa by reducing semen volume, increasing liquefaction time and direct toxic effect on them, by dissolved smoke constituents in seminal fluid.

Heavy exposure to alcohol and/or smoking ultimately deteriorated all aspects of semen quality. Synergistic effect of alcohol intake and smoking has been reported to be very detrimental to the reproductive health of an individual. [4],[5],[7],[24]


Asthenozoospermia is the most common anomaly of semen. Its presence can be a very subtle, 'early indicator' of reduction in the semen quality, which many a times gets overlooked, if the semen sample shows adequate sperm count and normal morphology.

Alcohol consumption produces progressive damage to sperm morphology and spermatogenesis; cigarette smoking produces sperm motility defect in light smokers with additive sperm morphology defects in moderate/heavy smokers. Deterioration in semen quality appeared in direct proportion to the quantity of alcohol intake and cigarettes smoked. Hence, male partners of infertile couples should strictly abstain from alcohol consumption and cigarette smoking.


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