Abstract
Objectives
To investigate clinical, demographic and psychological characteristics of infertile male smokers in northeast China.
Methods
Serum and semen samples were collected from infertile men. Semen analysis was performed according to conventional procedures. Serum follicle-stimulating hormone, luteinizing hormone and testosterone levels were quantified. Psychological anxiety and depression were evaluated by the self-rating anxiety scale (SAS) and self-rating depression scale (SDS), respectively.
Results
Both SDS and SAS scores were significantly higher in smokers (
Conclusions
Cigarette smoking has a negative effect on sperm viability and motility, and is associated with increased SDS and SAS scores.
Introduction
Smoking is a known risk factor in male infertility, but the effects of smoking on semen quality are unclear. In infertile men, cigarette smoking is associated with damaging effects on sperm density, viability, motility and morphology,1–6 as well as affecting semen volume.6–8 Smoking has also been shown to have detrimental effects on sperm parameters and seminal zinc levels in both fertile and infertile men,2,4,9 and heavy smoking can affect sperm concentrations.10,11 These effects are related to the both the number of cigarettes smoked and the duration of smoking. 2 Others have reported, however, that cigarette smoking has no effect on semen or sperm parameters.12,13 The effects of smoking on reproductive hormones are also unclear, with studies showing varying and contradictory effects on serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and total testosterone (TT) levels.3,8,14–16
Infertility can have psychological effects. 17 Infertile men are socially isolated, show more anxiety 18 and are more vulnerable to severe anxiety than fertile men. 19 Male partners in infertile couples experience greater psychological distress than fertile men, 20 and hormonal disturbances and the effectiveness of infertility management are related to mood disorders. 21 Additionally, psychological stress may be associated with the effect of cigarette smoking on the quality of semen, since lower sperm density and abnormal sperm are related to psychological stress, 9 and psychosocial anxiety is related to cigarette smoking. 22
The present study investigated clinical, demographic and psychological characteristics of infertile male smokers in northeast China. The relationships among psychological stress, smoking and quality of semen were also evaluated.
Patients and methods
Study population
The study enrolled men who sought treatment for infertility at the Andrology Outpatient Clinic, the Second Hospital of Jilin University, Changchun, China, between January 2013 and December 2014. A physical examination was conducted in each participant to determine age, height, weight, and testicular volume (assessed using a Prader orchidometer). All patients completed a detailed questionnaire regarding smoking history and frequency, marital history, education level, monthly income, working conditions and medical history.
The study protocol was approved by the ethics committee of the Second Hospital of Jilin University, Changchun, China, and all participants provided written informed consent.
Study parameters
Anxiety and depression were evaluated using the self-rating anxiety scale (SAS) and the self-rating depression scale (SDS), respectively, as validated for Chinese populations. 23 An SAS score ≥50 and SDS score ≥53 indicated anxiety and depression, respectively.
Semen analysis was performed according to procedures recommended by the World Health Organization, 1999. 24
From all patients, peripheral blood (5 ml) was collected using routine methods into sterile tubes without additives, stored at room temperature for 30 min, then centrifuged at 1000 g for 10 min. Serum was stored in sterile tubes at −20℃ until use. Serum FSH, LH and testosterone levels were quantified via electrochemiluminescence immunoassay (Roche Diagnostics, Mannheim, Germany).
Statistical analyses
Data were presented as mean ± SD or
Results
Demographic and psychological characteristics of infertile men from northeastern China, stratified according to tobacco smoking.
Data presented as mean ± SD or
Student’s
NS, not statistically significant (
Clinical characteristics of infertile men from northeastern China, stratified according to tobacco smoking.
Data presented as mean ± SD.
Student’s
Spearman’s correlation coefficient analysis revealed significant negative correlations between duration of smoking and sperm viability (
Discussion
The effect of smoking on semen quality in infertile men is unclear. The Practice Committee of the American Society for Reproductive Medicine reported that, according to available biological, experimental and epidemiological data, up to 13% of infertility can be attributed to cigarette smoking. 25 Cigarette smoking can accelerate the loss of reproductive function; 22% of semen parameters and sperm function are poorer in smokers than nonsmokers, and these effects are dose-dependent. 25 Testicular volume was significantly lower in smokers than nonsmokers in the present study, although this finding may be related to the varying aetiology of the study population.
Low-income individuals have been shown to consume more tobacco products than those with higher incomes. 3 There were no significant between-group differences in age, duration of infertility, height, weight, education level or monthly income in the present study, but sperm viability and motility were significantly lower in smokers than in non-smokers: these findings are in accordance with those of others.2,4–6 In addition, we found no significant between-group differences in semen volume, sperm count, or FSH, LH and testosterone levels, which is also consistent with other studies.8,16
Infertile men have an increased risk of psychological problems, and consideration of such issues is important in the diagnosis and treatment of infertility. Psychosocial interventions are efficacious for couples undergoing infertility treatment, since reducing psychological distress can improve clinical pregnancy rates. 26 The management of psychological factors has an important preventative role in treating infertility:27,28 psychological interventions from each person in a partnership can help each partner to support the other. 29
A key factor in the relationship between infertility and psychological anxiety is the duration of infertility and treatment, 30 since treatment-related psychological anxiety is linked to cigarette smoking level. 31 Both SDS and SAS scores were significantly higher in smokers than in nonsmokers in the present study, but they remained within the normal range. Correlation analysis revealed that both duration of smoking and number of cigarettes smoked per day were positively correlated with and SDS and SAS scores in the present study.
In conclusion, cigarette smoking has a negative effect on sperm viability and motility, and is associated with increased SDS and SAS scores in men from Northeast China. Infertile men with psychological anxiety tend to smoke more cigarettes than fertile men, therefore psychological effects should be taken into account in the treatment of male infertility. Infertile men who are smokers should be encouraged to stop smoking to improve their reproductive potential.
Footnotes
Acknowledgement
We are sincerely grateful to all of the staff of the Andrology Laboratory, Department of Urology, the Second Hospital of Jilin University, Changchun, China, for their excellent work.
Declaration of Conflicting Interest
The authors declare that there are no conflicts of interest.
Funding
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
