Epidemiology and occupational risk factors of male infertility based on 3,025 patients in Eastern Morocco during 2021-2023: a cohort study
Article information
Abstract
Objective
The objective of our study was to characterize the sperm parameters of men consulting for infertility in our fertility center.
Methods
The study included 3,025 patients investigated from September 2021 to July 2023. Demographic data, infertility risk factors, and the primary or secondary nature of infertility were recorded for each patient. The sperm parameters were analyzed according to World Health Organization (WHO) criteria (2021).
Results
The average age of the patients was 40 years. The average duration of infertility was 5.5 years. Primary infertility was noted in 2,736 patients (88.97%). The most common risk factors for infertility were occupational exposure, followed by varicocele. Lifestyle factors associated with male infertility included smoking (24.29%), alcohol consumption (12.49%), and high temperature exposure (30.08%). Spermogram abnormalities were observed in 78.71% of cases. Spermocytogram abnormalities were found in 63.1% of cases. Sperm count, morphology, total motility, and vitality below WHO (2021) reference values were found in 25.60%, 34.13%, 32.29%, and 62.46% of the analyzed samples, respectively. Seminal fluid analysis revealed oligozoospermia in 29.07% of cases, asthenozoospermia in 24.68%, and azoospermia in 17.56%. Oligo-astheno-necrospermia was the most frequently observed combined abnormality (10.0%).
Conclusion
This study showed a high rate of abnormal semen quality in male partners of infertile couples. Male infertility is often multifactorial and results in quantitative and/or qualitative sperm abnormalities.
Introduction
According to the World Health Organization (WHO), infertility is a disease of the reproductive system, defined by the failure to achieve a clinical pregnancy after 1 year or more of regular and adequate unprotected sexual intercourse [1]. Infertility has major public health, economic, and psychosocial consequences worldwide that cannot be ignored in Morocco [2]. According to the WHO, infertility affects 7-12% of men of reproductive age [3], with at least 30-40% of these cases caused by male factors. Recently, increasing attention has been paid to male infertility [4].
Semen analysis is a fundamental diagnostic tool in evaluating male fertility potential. In most cases, male infertility is linked to abnormalities in one or more semen characteristics [5]. Additionally, numerous authors have suggested that male reproductive potential and semen quality have declined since the 1990s [6].
According to a survey conducted by the Moroccan Society of Reproductive Medicine, through a poll carried out by the Averty Institute among 1,034 couples in Morocco, approximately 15-17% of couples of childbearing age are affected by infertility, representing no fewer than 825,000 people [2]. Male infertility remains a sensitive subject in Morocco, which limits scientific research in this area and highlights the need for further efforts in this direction.
We believe that knowledge regarding male infertility is lacking. Consequently, no epidemiological research on male infertility in the oriental population of Morocco has been conducted to date. This study may be helpful for clinicians (gynecologists, andrologists, and urologists, etc.) and researchers in gaining a concrete understanding of the problem and achieving comprehensive management of infertile couples. The aim of this study is to determine the clinical, etiological, and epidemiological characteristics of male infertility in the fertility unit of the University Hospital Center in Morocco.
Materials and methods
1. Subject recruitment
This study is descriptive and retrospective, with a focus on epidemiology and diagnostics, involving 3,025 records of patients seen in consultation in the fertility unit for conjugal infertility from September 2021 to July 2023. All the clinical and paraclinical characteristics studied have been analyzed. This study includes all patients presenting to the laboratory for semen analysis as a component of an evaluation of male infertility. All incomplete records were excluded from the study.
For the female partner, the investigations performed included hormone analysis, ultrasonography, and hysterosalpingography for tubal patency assessment. Table 1 provides the medical history of the female partners.
Data collection was based on a questionnaire containing all the parameters to be studied. To meet the objectives of our study, each patient was asked about the following parameters.
2. Semen analysis
According to WHO 2021 standards (6th edition), conventional semen parameters are a crucial test to evaluate male fertility potential by examining specific criteria. Masturbation was used to collect semen samples into a sterile plastic container in a closed room after 2-3 days of abstinence. Macroscopic and microscopic parameters of semen were assessed after liquefaction at 37°C.
Semen volume was quantified using a graduated pipette. The Computer-Assisted Sperm Analyzer (SCA; Microptic, Barcelona, Spain) was used to measure the microscopic parameters of sperm, and when necessary, dilutions were prepared using a diluent. Aliquots of the semen sample were transferred into a counting chamber. Following the most recent WHO recommendations, the percentage of motile sperm was graded using the following classification: A (rapid progressive motility [PR]), B (slow PR), C (non-progressive motility), and D (immotility). The eosin-nigrosin test was applied to samples to evaluate the viability of spermatozoa.
For morphological evaluation, sperm were stained with the Diff-Quick kit (Microptic). The morphological assessment was performed with a microscope. At least 100 spermatozoa were counted. David’s modified classification was used to identify normal or abnormal morphology using strict scoring standards.
The WHO 2021 (6th edition) defined normal values for semen as a volume of more than 1.4 mL and a pH of at least 7.2. Other criteria include sperm concentration ≥16 millions spermatozoa/mL, a total sperm count of 39 M/ejaculate, PR motility ≥30%, vitality ≥54%, and morphology ≥4% of normal forms according to David’s modified classification. The search for spermatozoa in the urine was carried out for patients with severe oligospermia, aspermia, or azoospermia who had described retrograde ejaculation [7].
3. Hormonal assay
Hormonal assays are useful in evaluating the functioning of the Leydigian and Sertolian compartments, as these compartments interact intricately to facilitate optimal spermatogenesis. The hormonal profile was evaluated using quantitative analysis of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. The levels of FSH, LH, and testosterone were measured in peripheral blood collected in a dry tube and assayed using the Architect ci8200 (Abbott Diagnostic, Macquarie Park, Australie).
4. Genetic analysis
Constitutional karyotype analysis and a polymerase chain reaction (PCR) search for Y chromosome microdeletions were performed. Chromosomal analysis was conducted on cultures of peripheral blood lymphocytes from patients, as described previously. The study of the Y chromosome was analyzed by multiplex PCR, using three pairs of primers specific to the azoospermia factor (AZF) a, AZFb, and AZFc regions.
5. Statistical assay
The data were evaluated using Statistical Software version 21.0 (SPSS Inc., Chicago, IL, USA). All numeric data are presented as the mean±standard deviation. Frequencies were expressed as percentages. Qualitative variables were shown as percentage and frequency, while quantitative variables were shown as mean±standard error of the mean (SEM). Descriptive statistical tests, including frequency tables, graphs, mean, median, and standard deviation, were used. The test statistics used to analyze the data were descriptive statistics and the chi-square test. The level of significance was P<0.05.
6. Ethical statements
This study was approved by the Research Ethical Review Committee of the Faculty of Medicine and Pharmacy of Oujda, Morocco (Approval code: 02/2023).
Results
The average age was 40 years, ranging from 22 to 65 years. The age group between 40 and 49 years was the most represented, with a percentage of 42% (Fig. 1). The age category between 30 and 39 constituted 33% of the population, followed by the age group between 50 and 59, which accounted for 17%. Then, 5% of individuals were in the 22 to 29 years age category.
Among 6,714 couples, 45.05% had male factors, 15.19% had female factors, 29.49% had a mixed origin of infertility, and in 10.26% of couples, the origin was idiopathic, which was classified as unexplained infertility.
The demographic characteristics of the patients are presented in Table 1. A total of 46.61% of the patients had a normal weight, and 36.99% were overweight. Over half (55.33%) of the patients were illiterate, followed by 27.47% with primary school education, 11.10% with high school education, and 7.73% with a graduate-level education. In terms of occupation, over one-third (6.38%) had no profession. The most representative professions were drivers, with 37.78% (n=1,143), followed by traders, with 16.95% (n=513). Builders, farmers, and teachers accounted for 6.64% (n=201), 5.05% (n=153), and 4.56% (n=138), respectively. Nearly 60.49% of the patients resided in rural areas, and 82.41% had a low socioeconomic status.
Smoking and alcohol consumption are among the factors and/or determining causes of male infertility. Smoking was reported in 735 patients, or 24.29% of cases, and alcohol consumption in 378 patients (12.49%). The average number of cigarettes smoked was 10.53±1.72 cigarettes/day. About 24.06% had diabetes, with the mean duration of the disease being 9.11±0.70 years. A total of 34.84% of the respondents were hypertensive, with the mean duration of hypertension being 10.62±4.63 years (Table 2).

Behavioral and anthropometric characteristics and main pathologies related to male infertility found in the past medical history of 3,035 patients
The majority (38.67%) did not have any history of adverse environmental exposure. However, 30.08% reported occupational exposure to high temperatures, 14.47% to pesticides, 10.47% to chemicals, and 6.28% to radiation. The mean duration of exposure was 8.41±3.82 years. Table 2 shows the major clinical and paraclinical findings in males with abnormalities in their sperm analysis.
Table 3 presents the clinical characteristics of the female factor in 3,025 infertile couples. Female infertility may be due to one or more causes, such as polycystic ovary syndrome, hormonal disorders, premature ovarian failure, genital infections, endometriosis, fallopian tube obstruction, congenital uterine anomalies, uterine synechiae, or other medical complications (diabetes and thyroid disorders).
For the female partner, specific investigations performed included hormone analysis, ultrasonography, and hysterosalpingography for tubal patency assessment.
Table 4 shows the mean and SEM of the semen quantitative variables: concentration, volume, sperm morphology, vitality, and motility. Compared to the WHO reference values, lower results were found in 9.71% of the cases (n=294) regarding sperm count in the ejaculate, motility in 25.09% (n=759), sperm concentration in 19.83% (n=600), morphology in 3.62% (n=384), semen volume in 10.51% (n=318), and vitality in 2.97% (n=90). The mean length of abstinence before the exam was 2.8 days (range, 2-4).
Fig. 2 shows the different semen abnormalities observed in the 3,025 males. A total of 12.49% (n=378) presented normal results (normozoospermia), while 89.15% (n=2,697) had abnormalities. The spermogram, interpreted according to reference values defined by the WHO 2021, was abnormal in 87.70% of cases. The abnormalities were quantitative: oligospermia in 28% of cases, azoospermia in 17%, and hypospermia in 11%; and qualitative: asthenospermia in 25% of cases, teratospermia in 14%, cryptospermia in 3%, and necrospermia in 3.5%. Oligo-astheno-necrospermia was the most common combination, observed in 10% of cases.
Table 5 presents the correlation between risk factors and male partner infertility. Infertile males were more likely to be overweight and smokers compared to their fertile counterparts (P=0.521 and P=0.057, respectively). Occupational exposure was higher among infertile males than among fertile individuals (P=0.621). Varicocele was significantly more common in the infertile group than in the fertile group (P=0.127). Diabetes and hypertension showed significant associations with male infertility (P=0.054 and P=0.011, respectively), and tobacco use was considerably higher among infertile males (P=0.057).
Discussion
Infertility is a widespread medical, social, and cultural issue whose prevalence remains a subject of debate. The epidemiology of male infertility in Morocco remains an understudied domain, despite its critical implications for public health and socio-economic stability. Our findings underline the urgent need for targeted research to identify risk factors specific to the Moroccan context, especially in the eastern region of Morocco, such as exposure to environmental pollutants, lifestyle choices, genetic predispositions, and the prevalence of untreated infections. Given the limited scope of existing studies, there is a significant gap in understanding the interplay of these factors in influencing male fertility outcomes.
This research emphasizes the importance of multidisciplinary collaboration between epidemiologists, urologists, reproductive endocrinologists, and public health policymakers. Such collaboration is pivotal for developing region-specific preventive strategies and diagnostic tools. Furthermore, raising awareness among researchers and health authorities about male infertility as a public health issue could catalyze the implementation of robust screening programs and enhance access to advanced reproductive technologies.
The present study showed a high rate of abnormal semen quality in male partners. The male causes are often multifactorial and result in a quantitative and/or qualitative anomaly of the sperm. There are geographical differences in the prevalence of infertility [7]. Worldwide, between 60 and 80 million couples are thought to be infertile. A total of 15% of couples of childbearing age seek assistance for suspected infertility [8]. Most studies agree that over the past few decades, there has been a remarkable decline in the fertility rate worldwide [1]. The data from the Moroccan Society of Fertility and Contraception showed that 800,000 Moroccans suffer from infertility, a figure that remains uncertain and is not supported by any epidemiological study [9].
Every year, there is an increasing trend in the annual number of couples consulting for infertility in our unit of assisted reproductive technologies. The reason for this increase is that people are becoming more interested in their reproductive health, especially in the population of the eastern region of Morocco [10]. Despite having the highest birth rate in the world, Africa still suffers from infertility, which affects 25% to 40% of the population and has substantial social repercussions, including disputes, extramarital sex, and depression [3].
Bringing a child home is one of the main goals of marriage in Morocco. Some countries view women as primarily responsible for infertility; however, our study revealed that approximately two-quarters of male partners have abnormalities in their semen, which may be a factor in these couples’ infertility. Indeed, andrology remains a field still unknown to the Moroccan population. In addition, in our society, sexuality remains a taboo subject, and the absence of procreation is primarily attributed to women. Moreover, the collection of sperm by masturbation, the first stage of exploration and therefore of medical care, is most often refused by patients.
According to a more recent meta-analysis, men are the only cause of infertility in 20% to 30% of cases and contribute to 50% of all cases [1]. Due to its high incidence, infertility is a global public health issue in many nations. In the current study, 49.2% of couples had a male factor, and the etiologies of male infertility were similar to those reported in earlier studies [2].
The study by Salas-Huetos and Aston [11] demonstrated that the highest rates of male infertility were seen in Africa, Central, and Eastern Europe, while the rate was low in North America, Australia, and Central and Eastern Europe. Unfortunately, in Morocco and the Middle East, the figures are imprecise due to cultural reasons.
As many as 59% in France [12], 35% in Nigeria [13], 26% to 32% in the UK [14], and about 36% in South Africa [15] were identified as having this condition. In Morocco, through a series of 1,265 infertile couples, the male factor was recorded at 45.2% [16]. However, this study has helped identify an unknown prevalence of male infertility in Eastern Morocco and determine a profile of sperm parameter alterations. The epidemiology of male infertility is still poorly understood in the eastern region of Morocco [10]. The current study shows how the semen parameters of Moroccan men differ depending on their sociodemographic variables.
The goal of this study was to describe the male infertility profile by analyzing sperm parameters in 3,025 male patients over 11 months, from September 2021 to July 2023, in the fertility unit at the University Hospital Center. Men’s lifestyle variables, such as smoking, drinking, stress, and obesity, as well as their age, may impact the quality of their sperm [17].
Worldwide, infertility affects 8-12% of couples of reproductive age. The couple’s fecundity appears to be influenced by age. It is widely recognized that male fertility declines with age [18]. In our study, the average age of our patients was 40.0±7.4 years, with extremes between 23 and 65 years.
This outcome was consistent with data in the literature. Three investigations, including two in Morocco in 2018 [16] and 2020 [10], and another in Senegal [19], indicated an average age of 39.9, 39, and 40 years, respectively, with extremes of 21 to 67 years. Moreover, our findings are similar to those from the Urology Center of Grand Yoff in Dakar in earlier years [20]. On the other hand, the average age of 40 years is higher than that reported by Lotti et al. [21], who found a mean age of 32 years and 4 months, with extremes of 20 to 58 years, in a sample of 609 patients.
Male sperm quality and fecundity have decreased in males aged 20 to 40 years over the past 10 years, although male fertility is less influenced by age [18]. Indeed, the environment could affect fertility through food, radiation, and endocrine disruptors. This impact would be mediated not by genetic modifications but rather by epigenetic variations in sperm DNA [22].
Concerning body mass index, 46.61% of our patients were normal (n=1,410), 36.99% (n=1,119) were overweight, and 14.47% (n=438) were obese. Santi et al. [23] showed that male fertility potential is reduced in individuals with increased body weight compared to normal-weight men. Obese men exhibited lower sperm concentration, total sperm count, PR and total motilities, and normal morphology compared to normal-weight subjects. Reduced sperm concentration in obese men was influenced by age, smoking, varicocele, and total testosterone serum levels in meta-regression analyses [23]. Several studies have reported a relationship between metabolic syndrome and semen parameters/male infertility [24].
In our study, the most frequent profession was trader, followed by driver. Rochdi et al. [25] discovered dramatically different findings, with workers accounting for 38% of the professional population and civil servants contributing 32%. Stress and environmental pollution are two examples of occupational risk factors that could explain why some occupations are more represented than others. In addition to being exposed to more insecticides and other pesticides over a longer period than other patients, farmers have been reported to have poor sperm quality. For painters, male fertility may be negatively impacted by toxic chemical compounds; thus, we advise using additional caution when handling them [26].
It has also been established that professions requiring prolonged sitting (e.g., drivers, teachers, construction workers, mechanics, accountants, nurses, technicians, and civil servants) influence spermatic parameters. It has been demonstrated that workstation temperature, especially for drivers, increases scrotal temperature, leading to a decline in male fertility. Additionally, studies have shown that individuals who drove for more than 3 hours each day experienced longer times to conception and changes in sperm quality [27]. A study indicated that smoking could negatively affect basic semen characteristics in a dose-dependent manner, while other studies did not observe any impact [28].
In the studied population, 23.90% of infertile men were smokers. Among them, 67.34% smoked up to 10 cigarettes per day, while 28.57% smoked more than 10 cigarettes daily. The deleterious effect of smoking involves the disruption of hormone levels by nicotine and other chemicals, thereby altering sperm parameters. Additionally, smoking damages the DNA of the germ line via oxidative stress. The oxidative stress generated by tobacco appears to be one of the main causes of sperm quality deterioration, primarily leading to DNA fragmentation and changes in testosterone and prolactin concentrations [29]. In this study, 12.29% of infertile men reported alcohol consumption.
Primary infertility was the main reason for consultation, representing 88.99% of cases, while secondary infertility accounted for 11.01%. Our findings correlate well with data from the literature, such as those from Kuwait [30].
Varicocele is the most common cause of male infertility. In infertile men, it is unilateral left in 85% to 90% of cases, unilateral right in 0.2%, and bilateral in other cases. This can be explained by the fact that the pressure in the left renal vein, where the left spermatic vein flows, is higher than in the vena cava, with also a longer left path. The medical history of our patients revealed that varicocele was the most frequent clinical abnormality, found in 261 (25.46%) of our patients. Varicocele was found in 42.7% of cases in Malekshah’s study in Iran [31] and in 75.7% of cases in a study in Nigeria [32].
The spermatogenic activity was characterized by maturation arrest and hypospermatogenesis, which usually present as oligospermia. Recent studies conclude that varicocele might affect all of the parameters in a semen analysis, such as concentration, motility, forward progression, and morphology. There is a significant correlation between varicocele ligation and an improvement in sperm characteristics and pregnancy rate [33]. The search for varicocele is fundamental in the clinical evaluation of a hypofertile man.
Idiopathic sperm abnormalities were found in 17.75% (n=182) of cases. It is important to point out that one of the main current hypotheses concerning idiopathic male infertility is its association with oxidative stress (OS). A total of 30% to 40% of infertile men have elevated levels of reactive oxygen species (ROS) in the seminal fluid [34].
The spermatogenic activity was characterized by maturation arrest and low spermatogenesis, which is usually present as oligospermia. Recent studies conclude that varicocele might affect all of the parameters in a semen analysis, such as concentration, motility, forward progression, and morphology. An improvement in sperm qualities and conception rate is significantly correlated with varicocele ligation. In the clinical assessment of a hypofertile male, the search for varicocele is essential. Idiopathic sperm abnormalities were in 17.75%. It is important to point out that one of the main current hypotheses concerning idiopathic male infertility is an attack related to OS, 30% to 40% of infertile men have elevated levels of ROS in the seminal fluid [11].
Most patients produced between 1 mL and 6 mL of ejaculate, which is considered typical. A semen volume of less than 1.5 mL was observed in about 10.34% of patients, which may indicate ejaculatory duct occlusion.
The mean of the quantitative variables identified in the patients’ semen analyses was also analyzed in our investigation. The observed mean volume was 2.64±1.1 mL, the mean concentration was 25.60±0.88 M/mL, the mean normal morphology was 34.13±1.93, the mean progressive motility was 32.29±0.77, and the mean vitality was 62.46±1.6. These findings support the varied infertility diagnoses of various studies and the potential impact of different risk factors and study regions on the infertility profile.
Abnormal semen quality was responsible for roughly 87.70% (n=899) of cases among male partners of couples, representing about three-quarters of the participants, and some individuals had multiple abnormalities. The partners of fertile men had to be pregnant within the previous 2 years. Fertile men were excluded only if they had a history of infertility [3].
One of the main causes of infertility is abnormal sperm motility, which prevents sperm from ascending to the female genital system to fertilize the oocyte. Intracytoplasmic sperm injection can be used to facilitate assisted pregnancy for male partners with asthenozoospermia. This high incidence of asthenozoospermia (24.68%) reflects the seriousness of male subfertility in our society, as sperm motility is the most important predictive criterion for the occurrence of a spontaneous pregnancy. The anomaly of motility may correspond to an abnormality in the structure of the spermatozoa or anomalies in their maturation during transport in the genital tract.
In our study, endocrine and genetic assessments (FSH, testosterone, and karyotype) were requested in the event of azoospermia or severe oligo-asthenozoospermia (<5 million/mL) and were found to be normal in 13% of cases. The impact of oxidative stress on sperm could also lead to a decrease in fertilization potential and embryonic development. This justifies the addition of antioxidant treatments to the therapeutic arsenal for male infertility, particularly in cases of idiopathic oligoasthenoteratospermia and in men undergoing medically assisted procreation [35].
Infertility is a serious health issue that affects both individuals and society. This study demonstrated that there are many different etiologies for infertility, many of which require assisted reproductive technology. The availability and cost of assisted reproductive technologies remain issues in Morocco, as they are in many other developing nations. This center in Oujda is the first public assisted reproductive technology unit in the eastern region of Morocco. Thus, to reduce the cost of infertility treatment for those affected, this research highlights the necessity for other comparable units to be implemented in low-income nations.
The importance of semen analysis as the initial test in the assessment of male infertility should also be emphasized in light of these findings. New advancements in semen evaluation are ongoing in the quest for an accurate diagnosis and management of male infertility. In addition, it would be useful to study the fertilizing capacity of spermatozoa in terms of quality, since both natural and assisted reproduction largely depend on this factor for the development of the embryo during the fertilization process. The assessment of oxidative stress and sperm DNA damage would significantly improve the typical sperm analysis profile and serve as diagnostic tools for evaluating male infertility, which must be considered during andrological workups.
The prevalence of infertility and patient demand is increasing due to new environmental and socioeconomic risk factors that affect the epidemiological characterization of infertility. The most relevant sociodemographic information on male fertility in Morocco’s eastern region has been analyzed in our study. The study’s findings can inform the clinician about the patient’s personal life in addition to their medical history, aiding treatment decisions. It will also improve public health strategies in Morocco. It seems that more comprehensive studies are recommended to examine factors that increase the risk of male infertility in the eastern region of Morocco to confirm the results of the current study.
Notes
Conflict of interest
All authors declare that they have no conflict of interest.
Ethical approval
The study received approval from the Research Ethical Review Committee at the Faculty of Medicine and Pharmacy of Oujda (reference 02/2023).
Patient consent
All participants provided written informed consent to take part in the study and were made aware of its scientific purpose.
Funding information
All authors state that no funding was provided for this study.