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BMJ Open
BMJ Open
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bmjopen
BMJ Open
2044-6055
BMJ Publishing Group BMA House, Tavistock Square, London, WC1H 9JR

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10.1136/bmjopen-2024-084236
bmjopen-2024-084236
Original Research
Sexual Health
1733
1506
Investigating the relationship between spermogram parameters and sexual desire in infertile men: a cross-sectional study from a tertiary centre in Iran
http://orcid.org/0000-0001-8546-8750
Amirjannati Naser 10Namirjannati@yahoo.com

http://orcid.org/0000-0002-5432-7311
Akhavizadegan Hamed 20h-akhavizadegan@tums.ac.ir

http://orcid.org/0000-0002-5869-213X
Mohazzab Arash 3Amohazzab@yahoo.com

http://orcid.org/0000-0001-8285-5413
Ghorbani Behzad 1Bhzghorbani@yahoo.com

http://orcid.org/0000-0003-4785-4065
Lotfi Razieh 4raziehlotfi@abzums.ac.ir

http://orcid.org/0009-0000-3502-9792
Fathalian Manizheh 5mahtab.fathi358@gmail.com

1 Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran (the Islamic Republic of)
2 Department of Urology, Tehran University of Medical Sciences School of Medicine, Tehran, Iran (the Islamic Republic of)
3 Department of Epidemiology, Iran University of Medical Sciences, Tehran, Iran (the Islamic Republic of)
4 Social Determinants of Health Research Center, Alborz University of Medical Sciences, Karaj, Iran (the Islamic Republic of)
5 Avicenna Fertility Center, Avicenna Research Institute, ACECR, Tehran, Iran (the Islamic Republic of)
ManizhehFathalian; mahtab.fathi358@gmail.com
None declared.

NA and HA contributed equally.

2024
13 9 2024
14 9 e08423613 1 2024
19 8 2024
Copyright © Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
2024
https://creativecommons.org/licenses/by-nc/4.0/ This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

Abstract

Background

Male factor infertility can affect spermatogenesis, sexual desire, and thus the quality of life of couples. The present study was conducted to investigate the relationship between spermogram parameters, and the score of sexual desire in infertile men.

Methods

This cross-sectional study was conducted on 315 infertile men referred to the Avicenna Infertility Center of Tehran (March 2022 to March 2023). The participants were selected based on the results of previous spermogram and hormonal tests recorded in their medical records. Eligible men completed the demographic information questionnaire and Hurlbert Index of Sexual Desire. A multivariable linear regression model was used to adjust the effect of variables on Hurlbert’s score.

Results

There was no significant relationship among sperm parameters (count, morphology, motility, vitality, concentration and DNA Fragmentation Index) and with sexual desire of infertile men. Education level, age of men and their partners, the duration of the marriage and duration of infertility did not have a statistically significant effect on sexual desire. However, economic status had an inverse effect on men’s sexual desire, with regression coefficients of 7.37 and 7.78 for medium and low socioeconomic levels compared with high (p<0.05).

Conclusion

Male sexual desire is primarily influenced by social factors rather than organic ones. Further multicentre prospective studies are recommended for more accurate results.

male infertility
sexual dysfunction
sexual medicine
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pmcStrengths and limitations of this study

Sexuality and infertility are both in the reproductive system, but until now the clinical relationship between the two had not been investigated, this is one of the strengths of our study.

The sperm parameters are constantly being reviewed and changed. And this is one of the limitations of the study.

Examining sexuality in couples of religious countries is still taboo and we faced difficulties in examining sexuality and completing the questionnaire.

Introduction

Infertility is defined as the failure to achieve a clinical pregnancy after 1 year or more of unprotected intercourse.1 It is assumed that male factors are responsible for approximately half of the cases and are mentioned as a solo cause of infertility in 35% of cases.2 The studies indicated that a man who fails at fertility is likely to evaluate himself as sexually inadequate and may experience temporary impotence and decreased libido.3 Many studies demonstrate that infertility may have a negative impact on the sexuality of the couple.4 A few studies have reported that the risk of sexual dysfunction increases with the level of impairment of semen quality.5 6 In a study in Iran, the prevalence of low desire sexual in infertile men was reported about 9.2%.7 Sexuality has a significant impact on the quality of life, and happiness of people.8 It is estimated that the number of patients with sexual problems is far more than the number of patients who refer to treatment clinics due to other health problems, while a small number of patients with sexual dysfunction refer to clinics.9 Based on the findings of the National Health and Social Life Study, sexual dysfunction in men includes unwillingness to have sex (13–14%), inability to achieve orgasm (7%), premature orgasm (30–32%) unsatisfaction with sex (8–10%), performance anxiety (17–19%) and dysfunction in achieving and maintaining an erection (7–9%) are defined.10 There is no universally accepted definition for sexual desire, despite the fact that it is a crucial sign of men’s sexual function. Sexual desire is often understood as a mental state, that is, triggered by either internal or external stimuli and consists of physiological, psychological, emotional and cognitive components to begin and sustain human sexual activity.11 The sexual function is closely related to their reproductive ability. Infertility is defined as the absence of pregnancy after 1 year of unprotected sex, and its prevalence among people of reproductive age is 15%, and this statistic is higher in developing countries.12 In Iran, the rate of infertility was reported as 13.2%, and the frequency of cases of male factor infertility has increased significantly in recent decades. A major part of this increase is related to sperm quality, as the most important indicator of infertility in men.13

In a study, it was determined that there is a decrease in sexual desire in one-third of men in infertile couples.14 It seems that infertility in terms of male factors carries the highest amount of stigma compared with other causes of infertility, which is the cause of more stress in these patients.15 Although the majority of research in the field of infertility focuses on women, very little is known about the effects of infertility and its diagnosis on men. The condition of infertility has physical, psychological and social repercussions on men.16 Men undergoing fertility treatments are more likely to experience sexual dysfunction. The diagnosis of infertility in men is considered a crisis for them which has destructive effects on their sexuality and leads to a feeling of sexual inefficiency in them. In infertile couples, sex turns into a forced and mechanical activity and the sexual behaviour of a person is deprived of feelings and provocative activities.17

Regarding the relationship between semen profile and sexual function, the available findings are very limited and contradictory. There is conflicting evidence about the link between sexual function and the severity of semen profile problem. One research suggests that there is no relationship at all,18 while other studies find a substantial one.5 19 Considering the major effect of infertility on the sexual function of couples, and the limitation of data on the relationship between semen profile and sexual function, as well as the relationship between semen profile and sexual desire in men, the present study was conducted to investigate the relationship between spermogram indices and sexual desire in infertile men.

Materials and methods

Characteristics of samples

This cross-sectional study was conducted to investigate the relationship between sperm parameters and sexual desire in infertile men referred to the Avicenna Infertility Center. The study population is all men who were referred to Avicenna Men’s Clinic of Infertility and Frequent Abortion Treatment Center due to infertility work-up in 2022–2023. By using the patients’ files, at the beginning, with the available sampling method, considering the inclusion criteria, the intended patients were contacted and after explaining the objectives of the study, they were invited to enter the study. Among them, 440 patients completed the Hulbert Sexual Desire Questionnaire, and after removing distorted and incomplete questionnaires, 315 eligible patients were included in the study. The samples were selected from infertile men with only male factors who were candidates for assisted reproductive treatments (In vitro Fertilization/Intra cytoplasmic sperm injection [IVF/ICSI]) and did not take special drugs. The researcher fully explained the objectives, necessity and process of the research obtained to the patients. The questionnaire was completed by the patients in a quiet room and individually, and they were told that they can ask the researcher for guidance if they have any doubts about the questions in the questionnaire. Then written informed consent was obtained from the participants at their first visit and is kept in their files. Demographic profile questionnaire and Hurlbert Index of sexual desire were completed by eligible patients. In order to ask any questions and to be informed about the results of the research, the email address and mobile number of the researcher were provided to the participants.

Inclusion criteria include unsuccessful attempts to conceive for at least 6 months, male factor infertility, the absence of systemic diseases including: diabetes, cardiovascular diseases, neurological diseases, chronic kidney diseases, cancers, spinal cord injury; fibromyalgia, lupus, thyroid diseases and other endocrine disorders, rheumatic diseases, no severe psychological disorders and depression, no current use of drugs affecting sexual function (such as antihistamines, antihypertensive drugs, cimetidine, metronidazole and metoclopramide), not undergoing surgical treatment 3 months before semen evaluation, absence of sexual dysfunction in the spouse and exclusion criteria included irreversible infertility, hypogonadism (testosterone levels <300 ng/dL), abnormal hormonal profile (including luteinizing hormone [LH], follicle stimulating hormone [FSH], testosterone, free T3 and T4, thyroid stimulating hormone [TSH] and PRL), azoospermia and secondary infertility. The study examined many demographic variables, including as age, education level, economic position, smoking and drinking habits, length of marriage, duration of infertility and body mass index. The present study aimed to survey many factors, such as libido and spermogram indices. The instrument of study was the Hurlbert Index of Sexual Desire. This questionnaire was created by Hurlbert, and it was used in many international researches. This questionnaire contains 25 questions, which measure the score of the subject’s sexual desire. The sexual desire questionnaire questions are widely used by therapists in clinics to measure sexual and marital problems and in scientific research. Each item is graded using a 5-point Likert scale. The marks of this questionnaire are obtained by summing the marks of 25 questions. The range of sexual desire score is 0–100, where a high score indicates a high level of sexual desire in the subjects. Hurlbert obtained 86% test–retest reliability of the sexual desire questionnaire.20 The validity and reliability of the translated Persian version were previously checked by Yousefi et al.21 The analysis of semen samples was done in the laboratory of Avicenna Center. The collection and evaluation of semen samples was done based on the guidelines of WHO, the sixth edition.22 All sperm analyses were evaluated by trained laboratory staff. In order to record the sperm parameters and sperm DNA Fragmentation Index (DFI), the results of the previous spermogram tests, which were analysed up to 3 months ago in the laboratory of Avicenna Center, were used. The sample size was calculated 18×15=270 by considering a 15% drop-out rate due to missing information, we conducted the study with 315 patients.

Patient and public involvement

To protect the privacy of patients, it was not appropriate to involve patients or the public in the design, or conduct, or reporting, or dissemination plans of our research.

Statistical analysis

The results were analysed using descriptive and inferential statistical tests with SPSS software V.25. Variable selection was performed using single-variable linear regression, including any outcome or confounding variable with a p value<0.2 in the multivariable analysis. Clinically significant confounders, such as male age, were included regardless of single-variable regression results. The significance level for multivariable regression was considered p<0.05.

Based on the rule of thumb for regression analysis, which recommends 15 observations per predictor.23 24 We calculated the necessary sample size for our study. With nine internally correlated variables (spermogram) and seven demographic variables, including one 3-level categorical variable (resulting in two dummy variables), we have a total of 18 predictors. The recommended sample size is 18×15=270. Considering a 15% drop-out rate due to missing information, we conducted the study with 315 patients.

Results

At first, 440 eligible patients were randomly selected based on their file number and using Excel. The objectives of the study were explained to the patients and the researcher asked them to complete the questionnaires. After removing distorted and incomplete questionnaires, finally, 315 qualified infertile men were included in the study. The mean age of the patients was 37.23 years (SD=5.30), and the mean score on the Hurlbert questionnaire was 72.70 (SD=11.79). A total of 151 patients (47.9%) belonged to the medium socioeconomic status group.

The demographic characteristics of the samples are presented in table 1. The socioeconomic status variable is calculated based on household income, housing status in terms of owner or tenant and the city of residence and then this variable was divided into three groups: low, medium and high.

Table 1 Demographic characteristic of patients

N=315		
Male age (years)	37.23 (5.30) (25–56)*	
Female age (years)	33.95 (6.21) (19–47)*	
Length of marriage (years)	6.28 (4.13) (1–25) *	
Length of infertility (years)	4.13 (3.86) (1–22)*	
Hurlbert score	72.70 (11.79) (30–97)*	
Male education	Non-university education	168 (53.3)†	
University education	147 (46.7)†	
Female education	Non-university education	126 (40)†	
University education	189 (60)†	
Socioeconomic status	High	82 (26)†	
Medium	151 (47.9)†	
Low	82 (26)†	
* Data are presented as Mmean (SD) (Rrange).

† Data are presented as frequency (Pper cent).

The description of spermogram variables including volume, count, concentration, morphology, progressive motility, total motility and vitality of sperm as well as DFI are shown in table 2.

Table 2 Descriptive report of patients’ spermogram indices and DFI

N=315	Mean (SD)	Minimum	Maximum	
Sperm volume (mL)	2.55 (1.36)	0.2	7	
Sperm count (106)	147.68 (103.43)	0.2	509	
Sperm concentration (106)	59.32 (29.35)	0.2	168	
Sperm morphology (%)	0.81 (0.82)	0	4	
Progressive motility (%)	25.47 (11.08)	0	55	
Total motility (%)	56.54 (15.09)	2	85	
Sperm vitality	90.33 (6.87)	42	99	
DFI (n=218) (%)	15.81 (10.55)	3	90	
DFIDNA Fragmentation Index

Examining the relationship between spermogram parameters and demographic characteristics with the level of sexual desire (Hurlbert Sexuality Questionnaire score) in the studied men is shown in table 3.

Table 3 Relationship between spermogram indices and demographic variables with Hulbert score of patients

N=315	Single variable analysis	Multivariable analysis	
Beta	P value	Unstandardised coefficients (beta)	95.0% CI for beta	P value	
		B	SE	Lower bound	Upper bound	
Male age (years)	−0.36	0.00	−0.05	0.24	−0.53	0.43	0.829	
Female age (years)	−0.24	0.02	−0.02	0.20	−0.41	0.36	0.902	
Length of marriage (years)	−0.13	0.41	0.38	0.35	−0.32	1.08	0.281	
Length of infertility (years)	−0.06	0.72	−0.31	0.37	−1.04	0.42	0.406	
Sperm count (106)	0.01	0.04	0.01	0.01	−0.01	0.03	0.549	
Sperm concentration (106)	0.03	0.21	0.07	0.04	−0.02	0.15	0.111	
Sperm morphology (%)	−0.31	0.70	−1.39	1.26	−3.87	1.09	0.271	
Progressive motility (%)	0.05	0.39	0.14	0.14	−0.13	0.42	0.308	
Total motility (%)	0.03	0.46	−0.18	0.12	−0.41	0.06	0.14	
Sperm vitality	0.09	0.36	0.08	0.15	−0.21	0.37	0.589	
Socioeconomic status	1=medium	1.63	0.22	7.37	1.96	3.50	11.24	<0.001*	
0=high	1=low	3.11	0.04	7.79	2.56	2.73	12.84	0.003*	
DFI (%)	−0.11	0.11	−0.09	0.09	−0.26	7.28	0.301	
Male education	0.43	0.75	3.51	1.91	−5.73	1.75	0.068	
Multivariable linear regression analysis was used, with a p value<0.2 considered significant for variable selection and <0.05 for statistical inference.

1=university education, 0=high school education.

* sSignificant relationship.

DFIDNA Fragmentation Index

The results of table 3 showed that the economic status has a statistically significant relationship with the Hurlbert Sexuality Score.

Discussion

This study aimed to analyse the relationship between sperm parameters and the libido index score of infertile men. Therefore, to adjust the psychological effects of infertility on the study, patients who had severe psychological problems or depression were not included in the study. Regarding the effect of androgens on sexual desires, only men whose testosterone, prolactin, LH and FSH levels were normal were included in the study. Thus, 315 eligible infertile men participated in the study. There was no statistically significant relationship between sperm parameters, and sexual desire scores in infertile men, especially after adjustment of potential confounding variables. The findings indicated that while economic status was negatively correlated with the sexual desire of infertile men, there was no significant relationship found between the sexual desire score of infertile men and demographic variables such as age, education level, length of marriage and duration of infertility. The strength of the conclusion of this study should be confirmed with a larger sample size and in other similar studies.

The diagnosis, and treatment process of infertility is associated with many emotional and physical challenges that may cause sexual dysfunction in men and women.3 The image of loss of masculinity is considered one of the important reasons for sexual desire disorder in infertile men.19 Men in infertile couples are more likely to experience erectile dysfunction, ejaculation disorders, decreased sexual desire and a decrease in the frequency of intercourse.25 Previous investigations have shown a significant correlation between hormone levels, namely plasma testosterone, in infertile men and the occurrence of sexual dysfunction.26 It was reported that psychological symptoms are more common in infertile men with only male factors compared with other causes of infertility.27

Socioeconomic status was included in the model as a categorical variable, using the high level as the reference indicator. Consequently, downgrading the variable from high to medium or low significantly resulted in an increase in the Hulbert score. In the same way, there is a trend toward the significant relationship between men’s education level and sexual desire (p=0.068). A recent study reported that household income among couples seeking assisted reproduction did not indirectly predict any domain of sexual well-being, including libido.28 According to the results of our study on the relationship between the economic status and the sexual desire of infertile men, it can be stated that this is a secondary finding and, perhaps the desire to have sex because of having children is higher among lower-income households in low-income countries. In addition, the patients referred to our centre had almost an acceptable level of socioeconomic status, however, further studies in infertile men with different socioeconomic levels are recommended.

A case–control study was conducted in 2020 to compare the symptoms of sexual dysfunction in men of infertile couples with fertile men and study whether the symptoms of sexual dysfunction in infertile men are related to hypogonadism. The results of the study showed that the symptoms of sexual dysfunction, including decreased libido and concern about the size and appearance of the testicles and penis (mainly in hypogonadal men) were more common in men of infertile couples, and these symptoms were related to androgen deficiency.26 In our study, hypogonadism and disturbed hormonal levels patients were excluded from the study. It was reported that men’s libido is more sensitive to a decrease in testosterone levels than erectile function.29

In a study that was conducted to investigate the severity of spermogram disorder and sexual dysfunction. The disorder was associated with psychopathological symptoms, particularly anxiety. A majority of erectile dysfunctions were also documented among men taking azoospermic drugs. Moreover, the prevalence of premature ejaculation and decreased libido in azoospermic men was significantly lower compared with fertile men (p=0.015).5 One of the most common cases of sexual dysfunction in this study was reported in azoospermic men who were not included in our study. Among the other reasons for non-alignment is the non-entry of people with psychological and anxiety symptoms into the study, which is one of the important factors in erectile dysfunction and sexual desire of the patients.

Another study aimed at comparing the prevalence of sexual dysfunction in infertile, and healthy couples was conducted at Cairo University Hospital. The results showed that the erectile function scores in the infertile men were significantly lower than the other group (p value=0.001), and the frequency of erectile dysfunction was higher among the husbands of infertile women.30 Infertility in men may cause feelings of guilt, being worthless and leading to depression.31 Psychological stress resulting from sexual intercourse with the intention of conception, as well as subsequent psychological issues such as worry and discomfort, have been shown to be linked to sexual dysfunction.5 32 In a study aimed at investigating the change in sexual desire, and sexual satisfaction among 200 infertile couples referring to the Fertility Health Research Clinic. A decrease in sexual satisfaction was recorded in 52.5% of patients, and this decrease had a statistically significant relationship with education level. In general, 45% of patients reported a simultaneous decrease in libido and sexual satisfaction. Men’s age and infertility cause had no significant relationship with their sexual satisfaction. Regarding sexual desire, there was no significant relationship among people with a recent diagnosis of infertility (in the last 3 months) and people with a previous diagnosis of infertility (p=0.75).27

Clinically, it can be concluded that the diagnosis and treatment of infertility do not always inevitably lead to the defective cycle of sexual dysfunction and low sexual desire. Our research, nevertheless, was restricted to a subset of infertile men referred to a single infertility centre. It is recommended that prospective investigations be carried out at multiple centres to examine alterations in sexual desire among infertile male and female partners, with a comparative analysis with fertile couples. Furthermore, sexual desire changes in terms of organic pathologies in infertile men and women should be evaluated. Another limitation of our study is that due to the higher prevalence of mental disorders such as depression and anxiety in infertile couples, people who mentioned a background of depression and anxiety were not included in the study, while the self-reporting bias of these patients seems undeniable. However, identifying risk factors for sexual dysfunction in infertile couples should be one of the important aspects of infertility management.

Conclusion

In this study, the relationship among sperm parameters and the level of sexual desire in infertile men was investigated, and the results showed that regardless of the hormonal effect and psychological issues that often exist in infertile men, there was no difference between sperm parameters, and the sexual desire score of infertile men. Additionally, the findings demonstrated a negative relationship between the economic position of infertile men and their sexual desire score by looking at the impact of demographic characteristics such as age, education level, length of marriage, length of infertility and economic status. Male sexual desire is primarily influenced by social factors rather than organic ones. However, further multicentre prospective studies are recommended for more accurate results to investigate the relationship between sperm parameters, and male libido in the fertile population and compare it with infertile men.

Acknowledgements

The authors of this article would like to thank and appreciate the cooperation of all the physicians and staff of the Avicenna Infertility Treatment Center who collaborated in this research. We are grateful for the cooperation of the patients who willingly participated in this study.

Data availability statement

Data are available upon reasonable request.

Review Process File
13 09 2024

Funding: The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

Prepub: Prepublication history for this paper is available online. To view these files, please visit the journal online (https://doi.org/10.1136/bmjopen-2024-084236).

Data availability free text: The data sets used and analysed during the current study are available from the corresponding author on reasonable request.

Patient consent for publication: Not applicable.

Ethics approval: The study approved by the Avicenna Ethics Committee the numbered as IR.ACECR.AVICENNA.REC.1401.020. Participants gave informed consent to participate in the study before taking part.

Provenance and peer review: Not commissioned; externally peer reviewed.

Patient and public involvement: Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.
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