Use of post‐thaw semen quality parameters to predict fertility of water buffalo (Bubalus bubalis) bull during peak breeding season

This study was designed to predict the fertility of water buffalo bull using post‐thaw semen quality parameters during peak breeding season. Thirty ejaculates were collected from five bulls with artificial vagina and cryopreserved. At post‐thaw, semen was analysed for motility parameters, velocity distribution, kinematics, DNA integrity/fragmentation, viability, mitochondrial transmembrane potential, morphology, plasma membrane and acrosome integrity. Data of 514 inseminations were collected for estimation of in vivo fertility. Pearson's correlation coefficients showed that progressive motility (PM), rapid velocity, average path velocity, straight line velocity, straightness, supravital plasma membrane integrity, viable spermatozoon with intact acrosome or with high mitochondrial activity were correlated with in vivo fertility (r = .81, p < .01; r = .85, p < .01; r = .64, p < .05; r = .73, p < .05; r = .57, p < .05; r = .88, p < .01; r = .84, p < .01 and r = .81, p < .01 respectively). Step forward multiple regression analysis showed that the best single predictor of fertility was PM. However, combinations of semen quality parameters to predict fertility were better as compared to single parameter. In conclusion, fertility of buffalo bull can be predicted through some of the post‐thaw in vitro semen quality tests during peak breeding season.     

High levels of oxidation–reduction potential in frozen-thawed human semen are significantly correlated with poor post-thaw sperm quality

This study examined the relationship between oxidation–reduction potential (ORP) in frozen-thawed semen and the post-thaw sperm parameters. Levels of ORP were measured in 25 samples from men presenting for routine infertility work-up and were expressed as millivolt (mV)/10⁶ sperm/ml. Frozen-thawed samples were examined for post-thaw total motility (TM%), progressive motility (PM%), total sperm count (TSC) and ORP. The cryo-survival rate (CSR) was calculated as post-thaw TM/pre-freeze TM × 100. Data are provided as median and interquartile range (25th and 75th percentiles). The post-thaw TM% (10.0% [4.00%, 15.1%]), PM% (5.88% [2.97%, 9.33%]) and TSC (12.5 [10.0, 17.5] × 10⁶ sperm) were significantly lower than the pre-freeze TM% (45.9% [32.9%, 59.1%], PM% (31.5% [24.4%, 40.0%] and TSC (120 [90, 250] ×10⁶ sperm) (p < .001). Post-thaw ORP (2.62 [2.52, 3.13] mV/10⁶ sperm/ml) was significantly higher than pre-freeze ORP (0.73 [0.54, 1.21] mV/10⁶ sperm/ml; p < .001). The CSR was 21.7% (11.3%, 31.9%). The post-thaw seminal ORP was negatively correlated with post-thaw TM% (r = −.5; p = .02), PM% (r = −.41; p = .03), TSC (r = −.60; p = .03) and CSR (r = −.52; p = .01). Increased levels of ORP are significantly correlated with poor post-thaw sperm quality and CSR.     

Comparison of Tris egg yolk‐based,Triladyl® and Optixell® extender on post‐thaw quality,Kinematics and in vivo fertility of Nili Ravi Buffalo (Bubalus bubalis) bull spermatozoa

Our objectives were to ascertain the comparison of Tris egg yolk‐based, Triladyl ^® and Optixell ^® extender on postthaw quality, CASA parameters and in vivo fertility of Nili Ravi buffalo (Bubalus bubalis) bull spermatozoa. Semen samples (n = 35) from five bulls were diluted in Tris egg yolk‐based, Triladyl ^® , Optixell ^® extender and frozen in 0.50 ml French straws. Postthaw sperm CASA motility (%) was higher (p < 0.05) in Optixell extender as compared to Triladyl and Tris egg yolk‐based extender. Although sperm progressive motility (%), morphology (%), average path velocity (μm/s), straight line velocity (μm/s), curvilinear velocity (μm/s), amplitude of lateral head displacement (μm), beat cross‐frequency (Hz), straightness (%), length of curvilinear path (μm), length of average path (μm), intact plasma and acrosome membrane (%), and DNA integrity (%) were higher (p < 0.05) in spermatozoa cryopreserved in Optixell ^® extender as compared to Tris egg yolk‐based and Triladyl ^® extender. The fertility rates (68.18%, 45.45%, 55.4%) were higher (p < 0.05) in buffaloes inseminated with semen doses frozen in Optixell extender than the Tris egg yolk‐based and Triladyl ^® extender respectively. It is concluded that Optixell ^® extender improves postthaw semen quality and fertility in Nili Ravi buffaloes.     

Diagnostics of DNA fragmentation in human spermatozoa: Are sperm chromatin structure analysis and sperm chromatin dispersion tests (SCD‐HaloSpermG2®) comparable?

Men affected with idiopathic infertility often display basic spermiogramme values similar to fertile individuals, questioning the diagnostic impact of the World Health Organization (WHO) thresholds used. This study explored sperm DNA fragmentation in single ejaculates from 14 fertile donors and 42 patients with idiopathic infertility providing semen for assisted reproductive techniques in a university fertility clinic. Each ejaculate was simultaneously studied for sperm DNA fragmentation by the flow cytometer‐based sperm chromatin structure analysis (SCSA) and the new light‐microscopy‐based sperm chromatin dispersion assay (SCD‐HaloSpermG2^®), before and after sperm selection for in vitro fertilisation with a colloid discontinuous gradient. The WHO semen variables did not differ between groups, but DNA fragmentation after SCSA (DFI) or SCD (SDF) was significantly (p < 0.05) higher in patients (DFI: 40.2% ± 3.0 vs. SDF: 40.3% ± 1.4) than in fertile donors (DFI: 17.1% ± 2.1 vs. SDF: 20.9% ± 2.5). Sperm selection led to lower proportions of DNA‐fragmented spermatozoa (DFI: 11.9 ± 1.7 vs. SCD: 10.0 ± 0.9, p < 0.05). The techniques output correlated highly and significantly (r² = 0.82). DNA fragmentation is confirmed as a relevant variable for scrutinising patients with idiopathic infertility, beyond the evidently insufficient WHO semen analyses. Since both techniques yielded similar results, the reduced necessity of complex equipment when running SCD ought to be considered for a clinical setting.     

Addition of pomegranate juice (Punica granatum) in tris‐based extender improves post‐thaw quality,motion dynamics and in vivo fertility of Nili Ravi buffalo (Bubalus bubalis) bull spermatozoa

The aim of the present study was to determine the protective effects of pomegranate juice in tris‐based extender on semen parameters, computer‐assisted sperm analysis (CASA) motion characteristics and field fertility of post‐thawed Nili Ravi buffalo (Bubalus bubalis) bull spermatozoa. Two consecutive ejaculates/collection from each of the five adult Nili Ravi buffalo bulls were collected with artificial vagina at 42°C for a period of 7 weeks, diluted in extender containing different concentrations of pomegranate juice (0.0%, 2.5%, 5%, 7.5% and 10%). Diluted samples were packed and frozen in 0.54 ml French straws. The addition of 10% pomegranate juice in extender significantly improved post‐thaw sperm morphology (%), motilities (CASA total motility, progressive motility (%) as well as VAP, VSL, VCL, STR, DAP, DSL) compared to the control group (p < 0.05). Plasma membrane, acrosome membrane and DNA integrity were significantly higher in extender with 10% pomegranate juice than the control group (p < 0.05). Field fertility rate (60.39% vs. 46.53%) was higher (p < 0.05) in extender with 10% pomegranate juice as compared to the control. It is therefore concluded that the addition of 10% pomegranate juice in tris‐based extender improves post‐thaw semen parameters, CASA motion dynamics and field fertility in Nili Ravi buffaloes.     

Expression of paraoxonase types 1, 2 and 3 in reproductive tissues and activity of paraoxonase type 1 in the serum and seminal plasma of bulls

The paraoxonases types 1, 2 and 3 (PON1, PON2 and PON3, respectively) are enzymes that degrade lipid peroxides, preventing oxidative damages relevant for male reproductive function. This study determined the expression of those three paraoxonases in reproductive tissues of bulls and evaluated correlations among the activity of PON1 in the serum and seminal plasma with breeding soundness parameters in bulls. The expression of PON1, PON2 and PON3 was characterised by RT‐PCR in samples of testicular parenchyma, vesicular glands and epididymis collected from three slaughtered bulls. All three paraoxonases were expressed in the testicular parenchyma, PON2 and PON3 were both expressed in the epididymis head and PON3 was also expressed in the epididymis tail. The PON1 activity was determined in samples of serum and seminal plasma from 110 bulls submitted to breeding soundness evaluation. There was a strong correlation (r = .90) between the activity of the PON1 in both serum and seminal plasma (p < .0001). The PON1 activity in the seminal plasma was positively correlated with ejaculate's colour, sperm mass activity (p = .04), motility, vigour and viability (all p < .01). Thus, PON1 may be a potential marker for sperm motility and viability in bulls.     

Study on correlation of sperm quality parameters with antioxidant and oxidant status of buffalo bull semen during various stages of cryopreservation

This investigation was carried out to study the correlation of sperm quality parameters with antioxidant and oxidant status of buffalo bull semen during various stages of cryopreservation. Semen samples were evaluated for sperm parameters (mass motility [MM], concentration [CON], progressive motility [PM], viability [VIB], acrosomal integrity [AI] and hypo‐osmotic swelling [HOS] response), antioxidants (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx] and total antioxidant capacity [TAC]) and oxidants (Lipid peroxidation [LPO] and reactive oxygen species [ROS]) at fresh, pre‐freeze and post‐thaw stages. Sperm parameters (PM, VIB, AI and HOS response) and antioxidants (SOD, CAT and TAC) were significantly (p < .05) reduced at fresh stage, and oxidants (LPO and ROS) were significantly (p < .05) increased at pre‐freeze and post‐thaw stages. At fresh stage, MM was negatively correlated with LPO (p < .05), and CON was positively correlated with SOD, TAC and CAT, negatively correlated with LPO and CAT was positively (p < .01) correlated with VIB and HOS response. At pre‐freeze stage, CAT was positively correlated with PM and AI (p < .05), and AI was negatively (p < .05) correlated with ROS. At post‐thaw stage, CAT was positively correlated with PM, VIB, HOS response and AI,, and LPO was negatively correlated with HOS, AI and VIB. The study of correlations of these parameters at different preservation stages with bull fertility may play an important role in developing models for predicting future fertility of bulls in the absence of conception rate data.     

Quality assessment of frozen bull semen with the precursor A-kinase anchor protein 4 biomarker

In this study, the quality of frozen bull semen was evaluated with the proAKAP4 level test. Sixty straws of frozen bull semen from various batches (n = 30) belonging to six bulls were used in the current study. The frozen bull semen samples were analysed in terms of proAKAP4 levels, sperm morphology and sperm movement parameters at hour 0 and hour 3 after thawing. The semen samples were divided into three groups according to the proAKAP4 levels: low concentration (<25 ng/10x10⁶ spermatozoa), moderate concentration (25 to 39 ng/10x10⁶ spermatozoa) and high concentration (≥40 ng/10x10⁶ spermatozoa). A positive correlation was found between the proAKAP4 level and total motility (TM₃), progressive motility (PM₃), VSL₃ and VCL₃ values obtained after the third-hour thermoresistance test (p < .05). There was a negative correlation between the percentage of sperm abnormal tail and the proAKAP4 level (p < .01). In addition, it was observed that the semen samples with proAKAP4 concentrations of 25 ng/10⁶ spermatozoa and higher preserved the TM₃ and PM₃ motility characteristics. In conclusion, the proAKAP4 has the potential to become a biomarker protein to evaluate in the quality analysis of frozen-thawed semen.     

Semiquantitative promoter methylation of MLH1 and MSH2 genes and their impact on sperm DNA fragmentation and chromatin condensation in infertile men

To investigate the semiquantitative methylation alterations of MLH1 and MSH2 and the possible association among methylation of MLH1 and MSH2, sperm DNA fragmentation and sperm chromatin condensation in idiopathic oligoasthenoteratozoospermic men. Seventy-five idiopathic infertile men and 52 fertile and/or normozoospermic men were included in the study. SDF was analysed using the TUNEL assay in semen samples of 100 men. Promoter methylation of MLH1 and MSH2 genes was assessed by semiquantitative methylight analysis in semen samples of 39 and 40 men respectively. Sperm chromatin condensation was evaluated using aniline blue staining in 114 men. MLH1 promoter methylation was positively correlated with the percentage of aniline blue positive spermatozoa (r = 0.401, p = 0.0188). On the other hand, MSH2 promoter methylation was negatively correlated with sperm concentration and total sperm count (r = −0.421, p = 0.0068 and r = 0.4408, p = 0.009 respectively). The percentage of aniline blue positive spermatozoa in the control group was significantly lower than in the OAT group (p < 0.0001) and negatively correlated with total sperm count (r = −0.683, p < 0.0001), progressive sperm motility (r = −0.628, p < 0.0001), total motility (r = −0.639, p < 0.0001) and normal morphology (r = −0.668, p < 0.0001). Promoter methylation profile of MLH1 and MSH2 genes may play role on sperm DNA packaging and conventional semen parameters respectively.     

Relationship between morphological abnormalities in commercial bull frozen semen doses and conception rate

Commercial doses of frozen bull semen for artificial insemination may have a certain percentage of morphological defects, despite being subject to prior selection. The aims of this study were to determine the prevalence of morphological abnormalities in commercial doses (n = 55, r = 2) of dairy and beef bulls, from AI Centers and to determine the possible existence of differences between them, regarding the percentage of abnormal spermatozoa. At least 200 spermatozoa per sample were evaluated using Bengal Rose stain (3% m/v) and light microscopy (×1000 magnification). The mean percentage of abnormal sperm samples from dairy breeds was 7.19% ± 4.91% and from beef breeds was 15.83% ± 9.28%. Significant differences between biotypes were found in the proportion of abnormal spermatozoa, abnormal heads and abnormal midpieces; it could be due to different selection pressure. It was observed that the percentage of abnormal spermatozoa was not a good fertility level predictor for the commercial samples of frozen bovine semen used in this study. In both biotypes, the midpiece abnormalities were the most frequent, mainly its distal flexion (compensable defect). This could be as a result of the effects of freezing and thawing on spermatozoa.     

Testicular thermoregulation,scrotal surface temperature patterns and semen quality of water buffalo bulls reared in a tropical climate

This study evaluated the capacity of thermoregulation and its consequences on the scrotal surface temperature patterns and semen quality of buffalo bulls raised in a wet tropical climate. Eleven water buffaloes were evaluated in the rainiest, in the transitional and in the less rainy season. Air temperature and humidity were consistently high, but the animals did not show thermal stress in any season. The scrotal temperature gradient of buffalo bulls using infrared thermography was described, and three parallel and decreasing thermal bands were characterised. Sperm quality (n = 176 ejaculates) was maintained in normal parameters over the periods. Pearson's coefficients showed that sperm volume and progressive motility were negatively correlated with ocular globe, epididymal tail and minimum scrotal temperatures (p < .01). Sperm membrane integrity was negatively influenced by increases in epididymal tail and minimum scrotal temperatures (p < .01). Ocular globe temperature also showed positive correlation with rectal, spermatic cord, and epididymal tail temperatures (p < .01). Therefore, even under high temperature and humidity, the thermoregulatory system was effective in preventing heat stress and the normality of scrotal surface temperatures, spermatogenesis and sperm maturation were maintained.     

Cryoprotectant effect of trehalose in extender on post‐thaw quality and in vivo fertility of water buffalo (Bubalus bubalis) bull spermatozoa

This study was designed to ascertain the cryoprotectant effects of different concentrations of trehalose [0 (T0), 25 (T25), 35 (T35), 45 (T45) mm ], egg yolk [20% (E20), 15% (E15) v/v] and glycerol [7% (G7), 5% (G5) v/v] in Tris‐citric acid‐based extender on post‐thaw quality and in vivo fertility of buffalo bull spermatozoa. Twenty‐five ejaculates were collected from five bulls and split into four parts. After that, the split ejaculates from each of the bull were diluted either in T0E20G7 (control) or T25E20G5 or T35E15G5 or T45E15G5 extender. Finally, the sperm suspension was frozen in 0.54‐ml French straws. Post‐thaw sperm total motility (%), progressive motility (%), rapid velocity (%), average path velocity (μm/s), straightline velocity (μm/s), curvilinear velocity (μm/s), linearity (%), plasma membrane and acrosome integrities (%) were higher (p < .05) in T45E15G5 extender as compared to other treatment groups and control. The fertility rate (56.8% versus 41.3%) was higher (p < .05) in buffaloes inseminated with semen doses cryopreserved in extender containing T45E15G5 combination of cryoprotectants than the control. In conclusion, addition of 45 mm trehalose along with 15% egg yolk and 5% glycerol in extender improves the post‐thaw quality and in vivo fertility of buffalo bull spermatozoa.     

Efficacy of antioxidant therapy on sperm quality measurements after varicocelectomy: A systematic review and meta‐analysis

Antioxidants were proved to be efficient to improve the quality of spermatozoa after varicocelectomy. We carried out a systematic review and performed a meta‐analysis to evaluate the efficacy of antioxidant therapy in sperm parameters' quality after varicocelectomy during 3 or 6 months' treatment cycle. During research, randomised controlled trials were searched by MEDLINE, EMBASE and the Cochrane Controlled Trials Register, and necessary parameters were compared between two groups after varicocelectomy. Finally, six studies including 576 patients were included in our meta‐analysis. As for sperm parameters, significant improvements of sperm concentration (p < .0001), sperm motility (p = .03), progressive sperm motility (p < .00001) and sperm morphology (p < .00001) were existed in antioxidant group 3 months after varicocelectomy. With regard to the 6 months' outcomes, sperm parameters were improved as well except sperm motility (p = .72) and progressive sperm motility (p = .57). Referring to pregnancy rate, no significant difference was existed between two groups (p = .36), and the FSH level of antioxidant group was lower than placebo group 3 or 6 months after varicocelectomy (3 months, p = .02; 6 months, p = .03). In conclusion, compared with the placebo, the antioxidant therapy after varicocelectomy can improve the quality of sperm parameters and construct a favourable living condition for spermatozoa by reducing FSH level.     

Apoptotic sperm biomarkers and the correlation between conventional sperm parameters and clinical characteristics

The principal aim of this retrospective study was to examine the relationship between sperm apoptotic biomarkers and the patient's biclinical characteristics, the conventional sperm parameters and the results of assisted reproductive technology. Sperm analysis, activated caspases, annexin V staining for phosphatidylserine (PS) externalisation and labelling assay for DNA fragmentation were assessed in 122 males of infertile couples. Fifty‐seven couples were allocated to the natural conception group, and 65 couples underwent IVF or ICSI. Semen of IVF/ICSI patients showed a higher proportion of apoptotic spermatozoa in their spermatozoa when compared with a natural conception group (p < .05). Sperm apoptotic biomarkers correlated with age, FSH, and conventional sperm parameters. DNA fragmentation correlated positively with the percentage of semen having externalised PS (r = .78, p = 0) and activated caspases (r = .71, p = 0). Patients without clinical pregnancy had higher frequency of DNA fragmentation, externalised PS and activated caspases compared to patients with clinical pregnancy (p < .001). The best specificity and greater sensitivity were obtained with the test of the DNA fragmentation compared to the other biomarkers. Among the apoptotic biomarkers, only DNA fragmentation was found to predict natural or assisted pregnancy better than conventional sperm parameters.     

Infrared thermography as a noninvasive method to assess scrotal insulation on sperm production in beef bulls

This study evaluated the thermoregulation and spermatogenic changes by scrotal temperature gradient using infrared thermography in testicular compromised bulls. Bulls were insulated (n = 6) for 72 hr and control animals (n = 3) remained without insulation during all the experimental period. Seminal evaluation was performed prior, at insult removal and once per week for 13 consecutive weeks. Mean temperature gradient in insulated animals was lower at the time of insulation removal compared to the week prior and after the insult (p < .05). Two weeks after insult, sperm motility was lower in insulated compared to control animals (p < .01) and spermatozoa total defects were higher in insulated compared to control animals (p < .05). Two and seven weeks after insult, the major defects were higher in insulated compared to control animals (p < .05). Scrotal temperature gradient showed a positive correlation with sperm mass motion (p < .01) and a negative correlation with ocular globe temperature (p < .01) in insulated animals. The infrared thermography can be used to evaluate ocular globe temperature in bulls; however, it is only effective to detect changes in scrotal temperature gradient at the insult removal.     

Freezability of water buffalo bull (Bubalus bubalis) spermatozoa is improved with the addition of curcumin (diferuoyl methane) in semen extender

Effects of curcumin as antioxidant in extender were evaluated on freezability of buffalo spermatozoa. Semen from each of the five bulls (n = 3 replicates, six ejaculates/bull, a total of 30 ejaculates) was diluted in Tris‐citric acid extender containing curcumin (0.5, 1.0, 1.5 or 2.0 mM) or control. At pre‐freezing and post‐thawing, total antioxidant contents (μM/L) and lipid peroxidation levels (μM/ml) were higher (p < .05) and lower (p < .05) respectively, with 1.5 and 2.0 mM compared to 0.5 and 1.0 mM curcumin and control. At post‐thawing, progressive motility (PM, %) and rapid velocity (RV, %) were higher (p < .05) with 1.5 mM compared to other doses of curcumin and control (except in case of RV, 1.5 was similar with 1.0 mM). Kinematics (average path velocity, μm/s; straight‐line velocity, μm/s; curved‐line velocity, μm/s; straightness, %; linearity, %), in vitro longevity (%, PM and RV) and DNA integrity (%) at post‐thawing were higher (p < .05) with 1.5 mM compared to control. At post‐thawing, supravital plasma membrane integrity (%) and viable spermatozoa with intact acrosome (%) were higher with 1.5 compared to 2.0 mM curcumin and control. We concluded that freezability of water buffalo spermatozoa is improved with the addition of 1.5 mM curcumin in extender.     

The presence of seminal plasma,especially derived from stallion semen,helps preserve chilled Asian elephant (Elephas maximus) sperm motility

The effects of seminal plasma (SP), derived from autologous, homologous and heterologous species (stallion, boar and dog) on chilled Asian elephant sperm quality, were determined. Semen was collected from eight males and samples with ≥30% motile spermatozoa were used in the study. Semen was diluted with Tris–glucose–egg yolk extender, supplemented with different SP types and preserved at 4°C for 48 hr. Experiment 1 (n = 31), showed that the presence of SP (autologous) helped to preserve sperm quality in terms of sperm motility and acrosome integrity (p < .05). Homologous SP did not result in better sperm quality than autologous SP. Heterologous SP from stallion provided higher sperm motility and velocities compared to autologous SP (p < .05). Experiment 2 (n = 14) determined the effect of different SP from four stallions. All stallion SP gave higher (p < .05) results for motile spermatozoa and sperm velocities than autologous SP. In conclusion, the presence of SP helps preserve Asian elephant sperm quality and stallion SP supports the motility of Asian elephant spermatozoa during cold storage.     

Evaluation of the role of L-arginine on spermatological parameters,seminal plasma nitric oxide levels and arginase enzyme activities in rams

The purpose of this study is to investigate the effects of L-arginine on spermatological parameters, seminal plasma nitric oxide levels and arginase enzyme activities. Fertile rams that are 2–3 years old and weighing 50–60 kg were used as material. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th, 72nd, 96th and 120th hours for the control group before L-arginine administration. For treatment groups, L-arginine was administered intraperitoneally at a dose of 5 mg kg⁻¹ bw⁻¹ and semen was collected at the time point described for the control group. Spermatological characteristics of semen samples (semen volume, pH, sperm motility, concentration and abnormal sperm rate), seminal plasma nitric oxide levels and arginase enzyme activities were determined. Increased seminal plasma nitric oxide level (p < .01), seminal plasma arginase activity (p < .01), semen volume (p < .05), semen mass activity (p < .05), sperm motility (p < .05) and concentration (p < .01) and decreased abnormal sperm rate (p < .05 and p < .01) were observed by L-arginine administration. In conclusion, it may be concluded that L-arginine application in rams during the breeding season may have positive effects on rams' reproductive performance.     

Effects of lead,cadmium, copper and zinc levels on the male reproductive function

This study aimed to investigate the effects of heavy metals on measures of male fertility. One hundred and two infertile men with occupational exposure and thirty fertile men were included in this study. Blood and urinary levels of lead, cadmium, zinc and copper were measured by atomic absorption spectrophotometry. Semen parameters and a motile sperm organelle morphology examination were also performed. Measures of hormonal levels, oxidation–reduction potential, DNA fragmentation index and chromatin condensation were assessed for all participants. Heavy metals levels, oxidative stress and DNA quality were significantly higher in the infertile group compared to controls. FSH and testosterone levels were lower in the infertile group. A urinary cadmium level was positively associated with abnormal sperm morphology (r = .225, p < .05). Normal morphology was inversely correlated with the duration of the exposure (r = −.227, p = .022). The blood lead level was positively related to the level of testosterone (r = .223, p = .031). Cadmium and lead blood levels were positively correlated with the level of chromatin decondensation (r = .528, p < .001; r = .280, p = .017). Our study showed that occupational exposure to heavy metals is very harmful to reproductive health. DNA quality and oxidative stress investigations must be recommended for reprotoxic exposed patients prior to in vitro fertilisation treatment.