Epidemiological characteristics and temporal trends of male infertility in Egypt (2012–2022): Analysis of 3,037 consecutive cases

ABSTRACT

Background

Male factors contribute to about half of global infertility cases, yet regional data are limited, particularly in Egypt.

Objective

To characterize the sociodemographic, clinical, seminal, and hormonal profiles of infertile Egyptian men and investigate their correlations.

Methods

We retrospectively analyzed the medical records of infertile men presented to a single busy andrology/infertility center in Egypt between June 2012 and May 2022. Demographic, clinical, seminal, and hormonal data were reviewed, and trends and correlations were assessed.

Results

Of 3,037 men, primary infertility accounted for 76.13%, with a median infertility duration of 4 years. Varicocele was observed in 66.47% of cases, predominantly second-degree. Asthenozoospermia (31.74%), oligoasthenozoospermia (20.78%), and azoospermia (9.12%) were the most frequent semen abnormalities. Median sperm concentration was 24 million/ml, progressive motility 25%, and normal morphology 10%. From 2012 to 2022, median sperm concentration declined from 24 million/ml to 18 million/ml (p = 0.2), progressive motility declined from 25% to 17% (p < 0.001), and normal sperm morphology declined from 10% to 5% (p < 0.001). The COVID-19 pandemic period (2020–2022) exhibited the most prominent reduction in sperm progressive motility (from 21% to 17%; p < 0.001). Smoking negatively correlated with all sperm parameters. Follicle-stimulating hormone and luteinizing hormone levels correlated negatively with semen quality and testicular volume but positively with infertility duration. Neither varicocele grade nor total testosterone levels correlated significantly with sperm parameters.

Conclusion

This study identified primary infertility, varicocele diagnosis and asthenozoospermia as predominant findings among infertile Egyptian men. Over a decade, temporal declines in sperm concentration, motility, and morphology were observed, exacerbated by the COVID-19 pandemic. Smoking and elevated gonadotropins negatively influenced semen quality and testicular volume, whereas testosterone levels and varicocele grade showed no significant correlation. These findings highlight the importance of developing integrated, region-specific strategies to address male infertility.

Introduction

The global prevalence of infertility is about 15%, with a male factor being observed in around 50% of infertile couples [1]. However, the prevalence of male infertility varies considerably across different geographical and ethnic groups [2]. Such regional disparities pose significant challenges in accurately determining the global epidemiological characteristics of male infertility [3]. Recently, Africa has witnessed an increasing prevalence of infertility, emerging as a global epicenter with a disproportionately higher burden compared to other regions [4,5]. In Africa, the proportions of primary and secondary infertility were almost equally reported (49.91% vs 50.09%, respectively) [6], with the highest prevalence of primary infertility in North Africa (70.56%). Oligozoospermia, asthenozoospermia, and varicocele have been reported as the most common findings in male factor infertility [6].

The etiology of male infertility varies across populations due to sociodemographic and environmental influences. In 30–45% of cases, the cause remains unidentified and is classified as idiopathic [7]. Other recognized causes include varicocele (14.8%), urogenital infections (5–12%), immunological factors (3.9%), cryptorchidism (8.4%), and sexual dysfunctions (2.4%) [7]. Additionally, genetic causes account for about 15% of all cases of male infertility [8].

Basic semen analysis is the keystone of male infertility evaluation. It plays a critical role in diagnosing absolute infertility conditions such as azoospermia and provides essential information for classifying the severity of male factor infertility [9,10]. Evaluation of infertile men from diverse ethnic and geographical backgrounds can offer valuable insights into region-specific risk factors that may influence semen parameters and overall male fertility, which are vital for improving the management of infertile couples and for advancing the broader field of reproductive medicine [11]. Nevertheless, there remains a scarcity of epidemiological data on male infertility in several regions, particularly in the Middle East and North Africa (MENA), including Egypt. Therefore, the objective of the present study was to characterize the sociodemographic, clinical, seminal, and hormonal profiles of infertile Egyptian men and to explore potential correlations among these variables.

Methods

Ethical approval and study design

This retrospective case series was approved by the Ethical Committee of the Faculty of Medicine, Sohag University, Sohag, Egypt (Soh-Med-22–04-41). The study involved a review of medical records of men who were evaluated for infertility at a single infertility center, Sohag, Egypt, between June 2012 and May 2022. In accordance with WHO definitions, primary infertility refers to couples who have never achieved a pregnancy after at least 12 months of regular unprotected intercourse, while secondary infertility applies to those who have previously conceived but are unable to achieve another pregnancy despite similar conditions [12].

Data collection and patient confidentiality

Records of all men who attended the andrology clinic for infertility evaluation during the study period were included, irrespective of semen quality. Exclusion criteria were incomplete records, active or recent (≤3 months) genitourinary infection, history of exposure to gonadotoxins (chemotherapy or radiotherapy), or ongoing fertility treatment at the time of evaluation.

All patient records were anonymized and coded to maintain confidentiality. Data were extracted into a structured Excel sheet, covering demographics (age, residence), infertility characteristics (type, duration, smoking status, sexual function, medical comorbidities, or prior reproductive surgeries), and, when available, partner details such as age and history of infertility or reproductive disorders.

Clinical and laboratory assessments

Clinical examination findings were reviewed from the records and the included components are assessment of the penis, testes, and spermatic cords, with particular attention to the presence and grade of varicocele. Varicocele was diagnosed and graded clinically according to the Dubin and Amelar classification system during physical examination [13]. Testicular volume was estimated clinically using a Prader orchidometer during physical examination. Secondary sexual characteristics such as overall body habitus, distribution of facial and body hair, and fat distribution were also documented. Clinical assessments were conducted by a single andrologist (RS), who had over 15 years of professional experience at the commencement of the study in 2012.

Laboratory data included results from baseline (pre-treatment) semen analysis as per the 5^th edition of WHO guidelines [12], specifically sperm concentration, motility, and morphology. Semen analysis was conducted following a standardized protocol. Patients were advised to maintain 2–7 days of sexual abstinence before providing a masturbated semen sample in a sterile container at the laboratory. The samples were allowed to liquefy at 37°C and are analyzed within one hour to determine semen volume, sperm concentration, motility, and morphology using standard procedures [12]. Baseline serum levels of key reproductive hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), total testosterone, and estradiol, were measured using chemiluminescence immunoassay [14]. Normal reference ranges were defined as: FSH 1.5–12.4 mIU/mL, LH 1.0–9.3 mIU/mL, PRL 2.58–21.4 ng/mL, total testosterone 3–10 ng/mL, and estradiol 7.63–52 pg/mL, according to the laboratory’s established standards.

The International Index of Erectile Function-5 (IIEF-5) questionnaire was included in the routine assessment of many patients because erectile function is an integral component of male reproductive health and can influence infertility evaluation and management. In the andrology clinic, the IIEF-5 has been routinely used since 2015 for patients reporting sexual concerns or when sexual function data were required for comprehensive infertility assessment, even in relatively young men. However, as this was a retrospective study covering a 10-year period (2012–2022), the IIEF-5 data were available only for about half of the cohort, reflecting gradual integration of standardized sexual function questionnaires into clinical practice rather than selective testing. This explains the partial yet systematic use of the IIEF-5 within the dataset.

Statistical analysis

Data were initially recorded and organized using Microsoft Excel (Microsoft Corporation, USA), and statistical analyses were performed using R Studio software (version 2022.02.3, Boston, USA) [15]. The distribution of continuous variables was assessed for normality using the Kolmogorov-Smirnov test, along with visual inspection of histograms and Q-Q plots. As the continuous variables were not normally distributed, they were summarized using the median and interquartile range (IQR; 25^th and 75^th percentiles). Comparisons between groups for continuous variables were conducted using the Wilcoxon rank-sum test. Categorical variables were presented as frequencies and percentages, and group comparisons were made using Pearson’s Chi-squared test or Fisher’s Exact Test, as appropriate. Given the non-linearity of data, generalized additive model (gam) was used to capture trends in sperm parameters over the study period, and locally estimated scatterplot smoothing (loess) was used to plot the trends. Associations between quantitative variables were evaluated using Spearman’s rank correlation coefficient. A p-value of less than 0.05 was considered statistically significant for all analyses.

Results

Socio-demographic characteristics and infertility profiles

A total of 3,037 infertile Egyptian men were included in this 10-year retrospective analysis (2012–2022). The median age was 32 years (IQR: 28–38). The majority were manual laborers (57.7%) and resided in suburban areas (66.2%). Cigarette smoking was reported in 25.2% of participants, with a median cigarette smoking index of 100 (IQR: 20–240), while 20.1% used waterpipes (shisha). Primary infertility accounted for 76.1% of the cases. The median duration of marriage was 4 years (IQR: 2–8), 20.5% of patients had biological children from the current marriage (median number of children: 1 [IQR: 1–2]; youngest child’s median age: 4 years [IQR: 2.5–6]). A previous marriage was reported by 229 patients (7.5%), with available duration data in 59 individuals (median: 15 years [IQR: 7.5–23.5]). Among 49 patients with recorded paternity status in a previous marriage, 17 (34.7%) had fathered children (median: 3 children [IQR: 2–5]). Female partners had a median age of 25 years (IQR: 22–30). The majority reported regular menstrual cycles (95.4%) and no identifiable cause of infertility (94.3%), with ovarian disorders (3.25%) being the most common female factor. A history of dysmenorrhea was noted in 1.4% of the partners (Table 1).

Table 1.

Sociodemographic, marital and infertility characteristics among the study population.

Sociodemographic, marital and infertility characteristics	N = 3,037	N1
Husband age (years)	32.0 (28.0, 38.0)	3,037
Occupation		3,027
Manual worker	1,746 (57.7%)
Working abroad	481 (15.9%)
Employee	463 (15.3%)
Farmer	187 (6.2%)
Businessman	114 (3.8%)
Unemployed	36 (1.2%)
Residence		3,032
Suburban	2,007 (66.2%)
Urban	546 (18.0%)
Rural	479 (15.8%)
Cigarette Smoking		3,017
Non-smoker	2,147 (71.2%)
Cigarette smoker	759 (25.2%)
Ex-smoker	111 (3.7%)
Smoking index (for cigarette)	100 (20.0, 240.0)	648
Other special habits		3,023
No	2,382 (78.8%)
Waterpipe	606 (20.1%)
Tobacco	23 (0.8%)
Alcohol	7 (0.2%)
Others	5 (0.2%)
Duration of current marriage (years)	4 (2.0, 8.0)	3,032
Have children from current marriage	598 (20.5%)	2,918
No. of children from current marriage	1 (1.0, 2.0)	598
Age of youngest child	4 (2.5, 6.0)	546
Previous marriage	229 (7.5%)	3,037
Duration of previous marriage (years)	15 (7.5, 23.5)	59
Have children from previous marriage	17 (34.7%)	49
No. of children from previous marriage	3 (2.0, 5.0)	17
Type of infertility		3,037
Primary infertility	2,312 (76.1%)
Secondary infertility	725 (23.9%)
Duration of infertility (years)	4.0 (2.0, 7.0)	3,034
Wife age (years)	25.0 (22.0, 30.0)	3,000
Menstruation		3,007
Regular	2,867 (95.3%)
Irregular	140 (4.7%)
Female cause of infertility		2,983
None	2,814 (94.3%)
Ovarian	97 (3.3%)
Pelvic	57 (1.9%)
Tubal	9 (0.3%)
Others	4 (0.1%)
Uterine	2 (0.1%)
Dysmenorrhea	41 (1.4%)	2,967
1 Median (IQR); n (%)

Clinical characteristics

Table 2 summarizes the clinical characteristics. Most patients reported normal sexual desire (76.4%) and potency (73.9%), with a median International Index for IIEF-5 score of 24 (IQR: 22–24). Erectile dysfunction was present in 8.2% of the cohort (median IIEF-5: 18 [IQR: 15–20]). Diabetes mellitus was documented in 55 patients (1.8%), of whom 34 were on insulin and 21 on oral hypoglycemics. Hypertension (0.5%), chronic renal disease (1.8%), and chronic liver disease (0.6%) were also observed. Previous varicocele surgery was reported by 30.5% of patients, and 0.9% underwent surgical sperm retrieval. Prior use of assisted reproductive techniques included intracytoplasmic sperm injection (3%) and intrauterine insemination (2.2%). A positive family history of infertility was reported by 8.4% of participants.

Table 2.

Clinical characteristics among the study population.

Characteristic		N1
I. History
Sexual history
Desire		3,037
Good	2,319 (76.4%)
Average	655 (21.6%)
Poor	63 (2.1%)
IIEF-5	24 (22.0, 24.0)	1,491
IIEF-5 among ED patients	18 (15.0, 20.0)	132
Frequency of intercourse (weeks)	3 (2.0, 3.0)	2,554
Medical history		3037
Diabetes Mellitus
Not diabetic	2,982 (98.2%)
Diabetic on insulin	34 (1.1%)
Diabetic on oral hypoglycemic	21 (0.7%)
Hypertension		3,037
Not hypertensive	3,023 (99.5%)
Hypertensive	14 (0.5%)
Other chronic illness		3,037
Free	2,946 (97.0%)
Renal	56 (1.8%)
Hepatic	19 (0.6%)
Cardiac	9 (0.3%)
CNS	3 (0.1%)
Chemotherapy	1 (0.03%)
Chest	1 (0.03%)
GIT	1 (0.03%)
Psychiatric	1 (0.03%)
Operative history		3,037
No	1,895 (62.4%)
Varicocele repair	927 (30.5%)
Oblique inguinal hernia	47 (1.6%)
Abdominal	29 (0.9%)
SSR	27 (0.9%)
Haemorridectomy	21 (0.7%)
Urinary	12 (0.4%)
Other	79 (2.6%)
ART history		3,037
No	2,879 (94.8%)
ICSI	90 (3.0%)
IUI	68 (2.2%)
Family history for infertility		3,037
Negative	2,781 (91.6%)
Positive	256 (8.4%)
II. Examination
General examination
Hair distribution		3,037
Masculine	3,033 (99.9%)
Feminine	4 (0.1%)
Fat distribution		3,037
Masculine	3,032 (99.8%)
Feminine	5 (0.2%)
Breast		3,037
Normal	3,032 (99.8%)
Lipidomastia	5 (0.2%)
Local examination
Right testicular volume (ml)	15 (14.0, 17.0)	2,943
Left testicular volume (ml)	15 (14.0, 17.0)	2,926
Right testicular abnormalities		2,987
Normal	1,790 (59.9%)
Hydrocele	811 (27.2%)
Small ( < 12 ml)	355 (11.9%)
Absent	19 (0.6%)
Abnormal consistency	12 (0.4%)
Left testicular abnormalities		2,963
Normal	1,824 (61.6%)
Hydrocele	797 (26.9%)
Small ( < 12 ml)	317 (10.7%)
Abnormal consistency	13 (0.4%)
Absent	12 (0.4%)
Varicocele	1,941 (66.5%)	2,920
Unilateral	441 (22.7%)
Bilateral	1500 (77.3%)
Right cord		2,912
Normal	1,379 (47.4%)
1st degree varicocele	142 (4.9%)
2nd degree varicocele	1,153 (39.6%)
3rd degree varicocele	224 (7.7%)
Absent	14 (0.5%)
Left cord		2,915
Normal	983 (33.7%)
1st degree varicocele	288 (9.9%)
2nd degree varicocele	1,425 (48.9%)
3rd degree varicocele	209 (7.2%)
Absent	10 (0.3%)
Epididymis		3,037
Normal	2,965 (97.6%)
Abnormal	68 (2.2%)
Absent	4 (0.1%)
Vas deferens		3,037
Both Felt	2,964 (97.6%)
Right felt	29 (1.0%)
Left felt	8 (0.3%)
Thin	24 (0.7%)
Not felt	12 (0.4%)

¹n (%); Median (IQR).

Abbreviations: ART: Assisted Reproductive Techniques; IIEF- 5: International Index of Erectile Function- 5 score; IUI: intrauterine insemination; ICSI: intracytoplasmic sperm injection; SSR: Surgical Sperm Retrieval.

Genital examination findings

More than 99% of patients exhibited normal secondary sexual characteristics. The median testicular volume was 15 mL bilaterally (IQR: 14–17). Right-sided abnormalities included hydrocele (27.2%), small testis (11.9%), cryptorchidism (0.6%), and abnormal consistency (0.4%). Left-sided abnormalities included hydrocele (26.9%), small testis (10.7%), cryptorchidism (0.4%), and abnormal consistency (0.4%). Varicocele was detected in 66.47% of patients, with most cases having bilateral varicocele (77.3%), and left-sided varicocele being more prevalent and of higher grades. Anomalies in spermatic cords, epididymis, and vas deferens were rare but documented (Table 2).

Semen and hormonal profiles

Semen analysis results are detailed in Table 3. Approximately, one-fourth (24.3%) of men had normal semen profiles according to the 5^th edition of the WHO manual of human semen analysis (12). The most common abnormality was asthenozoospermia (31.7%), followed by oligoasthenozoospermia (20.8%) and azoospermia (9.1%). Other abnormalities included isolated oligozoospermia (6.9%), oligoasthenoteratozoospermia (4.1%), asthenoteratozoospermia (2.1%), isolated teratozoospermia (0.7%), and oligoteratozoospermia (0.2%).

Table 3.

Seminal and hormonal characteristics.

Characteristic	N = 3,0371	N
Category of semen analysis		3,037
Normal	738 (24.3%)
Asthenozoospermia	964 (31.7%)
Oligoasthenozoospermia	631 (20.8%)
Azoospermia	277 (9.1%)
Oligozoospermia	209 (6.9%)
Oligoasthenoteratozoospermia	124 (4.1%)
Asthenoteratozoospermia	65 (2.1%)
Teratozoospermia	22 (0.7%)
Oligoteratozoospermia	7 (0.2%)
Sperm parameters among non-azoospermic patients		2760
Concentration (million/ml)	24 (8.0, 50.0)
Progressive motility (%)	25 (10.0, 40.0)
Total motility (%)	45.00 (30.00, 60.00)
Normal forms (%)	10 (5.0, 28.0)
Hormonal profile
FSH (mIU/ml)	4.7 (2.4, 9.6)	594
LH (mIU/ml)	3.9 (2.8, 6.0)	403
Total testosterone (ng/ml)	4.1 (2.8, 5.6)	399
Prolactin	13.1 (9.2, 18.3)	409
Estradiol (Pg/ml)	23.9 (15.8, 38.2)	115

¹n (%); Median (IQR).

Abbreviations: FSH: Follicle stimulating hormone, LH: Luteinizing hormone.

We re-classified sperm parameters of the study population using the latest updated version (6^th edition) of the WHO manual of human semen analysis and compared them against the 5th edition classes (Figure S1). There was a strong agreement ( > 80%) between the two editions (Adjusted Cohen’s kappa = 89.9%). The 6^th edition has a less strict motility threshold than the 5th edition (30% vs. 32% progressive motility). So, 158 athenozoospermic patients, 68 oligoasthenozoospermic patients, 3 oligoathenoteratozoospermic patients, and 1 asthenoteratozoospermic patient (5th edition) are classified as normozoospermic, asthenozoospermic, oligoterazoospermic, and asthenozoospermic in the new edition, respectively. On the contrary, the 6th edition has a higher threshold for sperm concentration than the older edition (16 mil/ml vs. 15 mil/ml). So, 21 normozoospermic, 44 asthenozoospermic, and 9 asthenoteratoospermic patients (5th edition) are classified as oligozoospermic, oligoasthenozoospermic, and oligoasthenoteratozoospermic in the 6^th edition, respectively.

Excluding azoospermic men (n = 277), the median sperm concentration was 24 million/mL (IQR: 8–50), progressive motility was 25% (IQR: 10–40), non-progressive motility was 15% (IQR: 10–25), and normal morphology was 10% (IQR: 5–28).

Hormonal data showed a median FSH of 4.7 mIU/mL (IQR: 2.4–9.6; n = 594), LH of 3.9 mIU/mL (IQR: 2.8–6; n = 403), total testosterone of 4.1 ng/mL (IQR: 2.8–5.6; n = 399), prolactin of 13.1 ng/mL (IQR: 9.2–18.3; n = 409), and estradiol of 23.9 pg/mL (IQR: 15.8–38.2; n = 115) (Table 3).

Comparison between primary and secondary infertility

As summarized in Table 4, men with secondary infertility were significantly older than those with primary infertility (median age: 37 vs. 30 years; p < 0.001), as were their partners (28 vs. 24 years; p < 0.001). Right testicular volume was slightly larger in the secondary infertility group (15 [IQR: 14–17] ml vs. 15 [IQR: 13–17] ml; p = 0.039), while left testicular size showed no significant difference (15 [IQR: 14, 17] ml for both; p = 0.1). The prevalence and grading of varicocele were similar between groups.

Table 4.

Study characteristics of primary versus secondary infertility.

Characteristic	Primary infertility		Secondary infertility		p-value2
	Parameter1	Total N	Parameter1	Total N
Husband age (years)	30.0 (27.0, 35.0)	2,152	37.0 (32.0, 43.0)	885	< 0.001
Wife age (years)	24.0 (21.0, 28.0)	2,126	28.0 (25.0, 34.0)	874	< 0.001
Right testicular size (ml)	15.0 (13.0, 17.0)	2,081	15.0 (14.0, 17.0)	862	0.039
Left testicular size (ml)	15.0 (14.0, 17.0)	2,066	15.0 (14.0, 17.0)	860	0.10
Right cord		2,053		859	0.8
Normal	975 (47.5%)		404 (47.0%)
1st degree varicocele	99 (4.8%)		43 (5.0%)
2nd degree varicocele	806 (39.3%)		347 (40.4%)
3rd degree varicocele	164 (8.0%)		60 (6.9%)
Absent	9 (0.4%)		5 (0.6%)
Left cord	2,055		860		0.4
Normal	710 (34.6%)		273 (31.7%)
1st degree varicocele	198 (9.6%)		90 (10.5%)
2nd degree varicocele	987 (48.0%)		438 (50.9%)
3rd degree varicocele	151 (7.4%)		58 (6.7%)
Absent	9 (0.4%)		1 (0.1%)
Varicocele	1,350 (65.6%)	2,059	591 (68.6%)	861	0.11
Category of semen analysis		2,152	885		< 0.001
Asthenozoospermia	642 (29.8%)		322 (36.4%)
Normal	529 (24.6%)		209 (23.6%)
Oligoasthenozoospermia	446 (20.7%)		185 (20.9%)
Azoospermia	233 (10.8%)		44 (5.0%)
Oligozoospermia	154 (7.2%)		55 (6.2%)
Oligoasthenoteratozoospermia	88 (4.1%)		36 (4.1%)
Asthenoteratozoospermia	37 (1.7%)		28 (3.2%)
Teratozoospermia	17 (0.8%)		5 (0.6%)
Oligoteratozoospermia	6 (0.3%)		1 (0.1%)
Sperm parameters among non-azoospermic patients				841
Concentration (million/ml)	24 (8.0, 50.0)		24 (10.0, 50.0)		0.2
Progressive motility (%)	25 (10.3, 40.0)		20 (10.0, 36.5)		0.013
Total motility (%)	45.00 (30.00, 60.00)		43.00 (28.00, 60.00)		0.063
Normal forms (%)	10 (5.0, 29.0)		10 (5.0, 25.0)		0.9
Hormonal profile
FSH (mIU/mL)	4.6 (2.4, 10.1)	469	4.9 (2.5, 8.6)	125	0.9
LH (mIU/mL)	4.1 (2.8, 6.7)	317	3.8 (2.7, 4.9)	86	0.041
Total testosterone (ng/ml)	4.1 (2.8, 5.6)	311	4.3 (2.7, 5.9)	88	0.7
Prolactin	13.3 (9.7, 18.4)	320	11.3 (8.1, 17.6)	89	0.11
Estradiol (Pg/ml)	22.3 (16.3, 35.3)	92	31.9 (14.6, 42.2)	23	0.2

¹Median (IQR); n (%).

²Wilcoxon rank sum test; Pearson’s Chi-squared test; Fisher’s exact test.

Azoospermia was more common in the primary infertility group (10.83% vs. 4.97%; p < 0.001), while asthenozoospermia was more prevalent among men with secondary infertility (36.38% vs. 29.83%; p < 0.001), who also demonstrated lower progressive motility (p = 0.013). Other semen parameters did not differ significantly. LH was higher in men with primary infertility (p = 0.041), while other hormonal levels were comparable.

Temporal trends in sperm parameters

Figure 1 and Table S1 show temporal trends in sperm parameters over the study period (2012–2022). A non-significant decline in sperm concentration was observed over the study period, from 24 million/mL in 2012 to 18 million/mL in 2022 (p = 0.2). Progressive and total motility dropped significantly from 25% to 17% (p < 0.001) and from 45% to 40% (p < 0.001), respectively. Normal sperm morphology also followed a declining trend, starting at 10% in 2012, peaking at 25% in 2014 and falling to 5% by 2022.

Figure 1.

Temporal trends in sperm parameters over the study period.

The COVID-19 pandemic period (2020–2022) exhibited a fluctuation in sperm concentration (19 million/ml in 2020, 13 million/ml in 2021, and 18 million/ml in 2022; p = 0.66), a prominent reduction in sperm progressive motility (from 21% in 2020, 15% in 2021, and 17% in 2022; p < 0.001), and a non-significant decline in normal sperm morphology (7% in 2020 and 5% in both 2021 and 2022; p = 0.16; Table S2 ; Figure S2). Among all studied years, the pandemic year 2021 showed the lowest sperm concentration (13 million/ml) and progressive motility (15%).

Correlation analyses

Correlation patterns between clinical, hormonal, and semen parameters are presented in Figure 2. Strong positive correlations were found between sperm concentration and progressive motility (r = 0.70, p < 0.001), total motility (r = 0.72, p < 0.001), and morphology (r = 0.69, p < 0.001). Smoking index was negatively correlated with all sperm parameters, particularly progressive motility (r = −0.52) and morphology (r = −0.54; both p < 0.001).

Figure 2.

Correlation matrix between sperm parameters, baseline, clinical, and hormonal parameters. p < 0.05*, p < 0.01**, p < 0.001***.

Testicular volumes correlated weakly but positively with sperm concentration and negatively with infertility duration. No significant correlation was observed between varicocele grade and semen parameters or hormonal levels. FSH and LH were inversely correlated with sperm quality and testicular size, while showing positive correlations with age, smoking, and infertility duration. Prolactin had weak negative correlations with age and duration of infertility. Total testosterone showed minimal correlations with sperm parameters. Strong inter-hormonal correlations were noted between FSH and LH (r = 0.76, p < 0.001), and moderate correlations between LH and testosterone (r = 0.42) and FSH and testosterone (r = 0.28).

Discussion

In this retrospective study, we analyzed data of 3,037 infertile Egyptian men over a 10-year period, representing one of the largest and most inclusive single-center investigations of male infertility conducted in the MENA regions. Although a larger sample size was reported by Akang et al. in a study of 17,292 men from Nigeria and South Africa, their analysis was only confined to semen parameters [16]. In contrast, a multidimensional assessment was undertaken in the present study, including correlation analyses and longitudinal trends over a decade.

The median age at presentation (32 years) aligns with findings from Saudi Arabia [17], the United Arab Emirates [18], Kuwait [19], and Iraq [20] but lower than in Sudan (37 years) [21], South Africa (38 years), and Nigeria (42 years) [16], reflecting regional differences in awareness and healthcare access. Cigarette smoking was reported in 25.2% of cases, which is comparable to the national prevalence of 22% in Egypt [22]. Other forms of smoking, including shisha, were reported by 21.3% of participants.

Variations in smoking prevalence among infertile men across the region have been reported, ranging from 12.5% in Emirati patients [16] to 40.8% in Kuwaiti populations [19]. The prevalence of primary infertility in this cohort was 76.1%, in line with findings from Kuwait (78.6%) [19] and Saudi Arabia (80.5% and 88.7%) [17,23]. A meta-analysis by Abebe et al. reported the highest prevalence of primary infertility in North Africa among African regions (70.56%; 95% CI: 64.91–76.2%) [6]. The predominance of primary infertility in this cohort may also be attributed to the hospital-based design and referral bias toward couples with no prior conception who seek specialized andrology evaluation.

Varicocele was identified in two-thirds of patients, being bilateral in three-quarters of them, a prevalence higher than in northern populations [24,25] and Indian men [26], yet aligns closely with rates observed in Kuwait (86%) [17,19]. The relatively high rate of bilateral varicocele in this cohort may reflect potential regional or genetic influences. Chronic exposure to elevated temperatures and occupational heat stress can impair testicular thermoregulation and venous drainage, predisposing to bilateral venous dilatation [27,28]. Despite this, no statistically significant correlation was found between varicocele grade and semen parameters, consistent with previous reports [25,26].

A normal semen profile was identified in 24.3% of patients, a proportion that aligns with the European Association of Urology’s estimated range of 15–30% for unexplained male infertility [29]. Asthenozoospermia was the most common abnormality, observed in 31.7% of the cohort and more frequently among those with secondary infertility. A median sperm concentration of 24 million/mL was reported, which was comparable to the 25 million/mL reported among Nigerian men, but lower than the 41 million/mL among South African men [16]. Median progressive motility (25%) was found to lie between the 15% reported in Nigeria and the 40% reported in South Africa, while sperm morphology (10%) was similar to the 9% median reported among South African men [16]. Azoospermia was found in 9.1% of patients, consistent with international estimates of 10–15% [30,31], and was nearly twice as prevalent among men with primary infertility compared to secondary infertility (10.8% vs. 5%).

When compared to Western and Southeastern populations, our findings reveal notable differences in semen parameters. Our median sperm concentration of 24 million/mL was lower than the 98 million/mL reported among infertile men in South Europe [32], the 49 million/mL among unselected Western men (North America, Europe, and Australia) in a recent global meta-analysis [33], and the 40–52 million/mL observed in a large cohort of Chinese infertile men [34]. Median progressive motility (25%) was notably lower than the 38% reported in the South European cohort and the 33–38% among Chinese infertile men. Sperm morphology (10%) was similar to the 8% median normal morphology reported in the South European study. These comparisons suggest that while MENA semen parameters fall within the lower range of global values, they reflect broader international trends of declining sperm quality, particularly when compared to Western populations where the global meta-analysis documented a 51.6% decline in sperm concentration from 1973 to 2018 among unselected men [33]. Hormonal profiles indicated that the median levels of FSH, LH, prolactin, total testosterone, and estradiol were within normal ranges, which is consistent with reports from Saudi Arabia [17,23]. These findings are also comparable to those from Iraq, where normal FSH, LH, and testosterone levels were reported, but with elevated prolactin levels [20]. In the present study, LH levels were found to be higher among men with primary infertility, supporting observations from Nigeria [35] and Saudi Arabia [23]. Similarly, in a Chinese study of 338 subfertile men, baseline hormonal profiles showed FSH, LH, and testosterone levels within normal reference ranges [36]. An Italian multicenter study of 251 men with idiopathic infertility also reported baseline FSH and LH levels within normal limits for men with asthenozoospermia, though men with oligozoospermia showed elevated FSH, and those with non-obstructive azoospermia demonstrated markedly elevated FSH and LH with reduced testosterone [37]. A US study of 457 male infertility patients found that the traditional laboratory reference range for FSH (1.4–18.1 IU/L) may be too broad, as FSH levels above 4.5 IU/L were significantly associated with impaired semen parameters, suggesting that ‘normal’ FSH levels in infertile men may require redefinition [38]. These findings collectively suggest that hormonal levels within conventional reference ranges are common in infertile men with milder forms of spermatogenic dysfunction, while significantly elevated gonadotropins typically indicate more severe testicular impairment.

Significant negative correlations were observed between FSH and LH with testicular volume and sperm parameters, suggesting a state of hypergonadotropic hypogonadism in affected individuals. These results are in agreement with previous studies that have identified gonadotropins, particularly FSH and LH, as more reliable markers of testicular dysfunction than total testosterone [39,40]. Notably, total testosterone did not correlate significantly with semen parameters or testicular volume, which supports the conclusions of Liu et al., who demonstrated that testosterone levels did not distinguish between azoospermic patients with positive versus negative testicular biopsy findings [39].

A gradual decline in sperm quality was documented over the study period, from 2012 to 2022. Sperm concentration, progressive motility, and normal morphology declined by 28%, 32%, and 50%, respectively. Similar trends were reported in Nigeria and South Africa, i.e., a 13% and 7% decline in sperm concentration was observed over a decade [16]. Several additional studies and systematic reviews have reported consistent downward trends in sperm concentration and motility [41–48]. The COVID-19 period exacerbated this decline, particularly in progressive motility (from 21% to 17%) and morphology (from 7% to 5%). The pandemic year 2021 specifically witnessed the worst sperm concentration (13 million/ml) and progressive motility (15%). These findings are in line with other reports documenting adverse effects of SARS-CoV-2 infection or associated stressors on male reproductive function [49–52].

Despite a visible decline in sperm concentration, the change was not statistically significant, whereas the smaller decline in motility was highly significant. This likely reflects both statistical and biological factors. Statistical significance is influenced not only by the magnitude of change but also by data variability. Although sperm concentration declined by approximately 25% (from 24 to 18 million/mL), this change did not reach statistical significance (p = 0.2), likely due to the wide interquartile ranges (6–50 million/mL across both time points), which reflect substantial between-subject variability and reduce statistical power. In contrast, progressive motility exhibited a smaller absolute decline (from 25% to 17%, an 8-percentage point reduction), yet this change was highly significant (p < 0.001). This observation likely reflects both statistical consistency and physiological sensitivity. Motility is more sensitive to oxidative and metabolic stress, and its values were less variable across the cohort, allowing clearer detection of a consistent decline. These findings suggest that motility may serve as an earlier and more consistent marker of deteriorating sperm function than concentration. Moreover, the decline in sperm concentration observed over time may reflect the combined influence of several environmental and lifestyle factors. Rising rates of obesity, cigarette smoking, sedentary habits, and exposure to environmental heat and pollutants are all known to impair spermatogenesis through oxidative stress, hormonal dysregulation, and increased scrotal temperature. Urbanization and occupational exposures may also contribute to this deterioration. Although these variables were not systematically assessed in the present retrospective dataset, their cumulative effects likely underlie the temporal decline in semen quality observed in this population.

Smoking index correlated negatively with all major sperm parameters, confirming prior evidence of tobacco’s adverse effects on spermatogenesis [53–56]. A moderate inverse association between infertility duration and testicular volume paralleled findings from Boeri et al. [57]. Associations of smoking with gonadotropins suggest possible endocrine compensation, as previously proposed [58]. Additionally, a strong inter-correlation between FSH and LH, and a moderate positive correlation with total testosterone, were consistent with hormonal interaction patterns [36].

Despite its strengths, such as a large sample size and comprehensive clinical and temporal data, the study has several limitations. First, it was conducted retrospectively at a single infertility center and lacked a fertile control group for comparative analysis. Second, broader risk factors (e.g. occupation, body mass index, environmental exposures) and management-related data were inconsistently documented in the medical records. Third, although azoospermia was identified based on semen analysis findings, comprehensive etiological classification, such as differentiation between obstructive and non-obstructive types, genetic testing, or testicular biopsy, was not uniformly available across the cohort. This reflects the retrospective nature of the study and variability in diagnostic protocols over time. To avoid introducing bias from incomplete or inconsistent data, we did not include subgroup analyses based on partial etiological workups. We acknowledge this as a limitation and recommend that future prospective studies incorporate standardized diagnostic pathways to better characterize the clinical and biological distinctions among azoospermic men. Fourth, sperm parameters were initially classified as normal or abnormal based on the lower fifth percentile (with 95% confidence interval) from the WHO 2010 (5th Edition) criteria [12]. To address this, we re-classified the data using the revised reference values from the WHO 2021 (6th Edition) [59], which better reflect current standards. Finally, the limited availability of regionally comparable studies restricted the extent of benchmarking.

Notwithstanding these limitations, the study’s primary aim was to characterize descriptive and temporal epidemiological patterns within this clinical cohort, rather than to investigate population-level determinants or causal mechanisms.

Conclusion

In this large retrospective cohort of 3,037 infertile Egyptian men, primary infertility was found to account for approximately three-quarters of the cases. Over the 10-year study period, declining trends in sperm concentration, progressive motility, and normal morphology were observed. Negative correlations were observed between smoking index and all major sperm parameters, underscoring the detrimental impact of tobacco exposure on male reproductive function. Despite the high prevalence of varicocele in this cohort, no statistically significant correlation was detected between varicocele grade and semen quality.

These findings contribute important epidemiological and clinical insights into male infertility in the MENA region. It is recommended that future studies be conducted using prospective, multicenter designs with control populations to better define diagnostic thresholds and improve clinical management strategies for male infertility in this region.

Author contributions

The roles of authors are listed in accordance with the Contributor Role Taxonomy (CRediT) [60]. RS, Conceptualization, Methodology, Investigation, Resources, Writing – Review & Editing, Supervision, Project administration. MAE, Methodology, Software, Data Curation, Formal analysis, Visualization, Writing – Original Draft. IRS, Software, Data Curation. TAAH, Writing – Review & Editing. PS, Writing – Original Draft, Writing – Review & Editing. SD, Writing – Original Draft, Writing – Review & Editing. RH, Writing – Review & Editing. All authors reviewed and accepted the final draft.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Ethics approval and consent to participate

This retrospective case series was approved by the Ethical Committee of the Faculty of Medicine, Sohag University, Sohag, Egypt (Soh-Med-22–04-41)

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/20905998.2025.2590924

Patient consent statement

As it is a retrospective study involving medical records, consent statement does not apply for this study.