Inducing Mn defects within MnTiO3 cathode for aqueous zinc-ion batteries.

Layered manganese-based cathode materials are considered as one of the promising cathodes benefit from inherent low manufacturing cost, non-toxic and high safety in aqueous zinc-ion batteries (AZIBs). However, the sluggish reaction kinetics within layered cathodes is inevitable due to the poor electrical/ionic conductivity. Herein, MnTiO3 is reported as a new cathode material for AZIBs and in-situ induced Mn-defect within MnTiO3 during the first charging is desirable to improve the reaction kinetics to a great extent. Additionally, DFT calculations further demonstrate that MnTiO3 with manganese defects exhibits a uniform charge distribution at the defect sites, enhancing the attraction towards H+ and Zn2+ ions. Furthermore, it performs good cycling stability which can obtain 115 mA h g-1 even at 400 mA g-1 after 450 cycles and the discharge capacity reaches up to 233.8 mAh/g at 100 mA g-1 when Mn-defect MnTiO3 was employed as the cathode. This research could provide a new method for the development and mechanism research of cathode materials for AZIBs.

Two-Dimensional Transition Metal Boron Cluster Compounds (MBnenes) with Strain-Independent Room-Temperature Magnetism.

Two-dimensional (2D) metal borides (MBenes) with unique electronic structures and physicochemical properties hold great promise for various applications. Given the abundance of boron clusters, we proposed employing them as structural motifs to design 2D transition metal boron cluster compounds (MBnenes), an extension of MBenes. Herein, we have designed three stable MBnenes (M4(B12)2, M = Mn, Fe, Co) based on B12 clusters and investigated their electronic and magnetic properties using first-principles calculations. Mn4(B12)2 and Co4(B12)2 are semiconductors, while Fe4(B12)2 exhibits metallic behavior. The unique structure in MBnenes allows the coexistence of direct exchange interactions between adjacent metal atoms and indirect exchange interactions mediated by the clusters, endowing them with a Néel temperature (TN) up to 772 K. Moreover, both Mn4(B12)2 and Fe4(B12)2 showcase strain-independent room-temperature magnetism, making them potential candidates for spintronics applications. The MBnenes family provides a fresh avenue for the design of 2D materials featuring unique structures and excellent physicochemical properties.

Association between MTHFR c.677C>T variant and erectile dysfunction among males attending fertility clinic.

ABSTRACT: Genetic risk factors have been shown to contribute to the development of sexual dysfunction. However, the role of methylenetetrahydrofolate reductase (MTHFR) gene variants in the risk of erectile dysfunction (ED) remains unclear. In this study, we recruited 1254 participants who underwent ED assessed by the International Index of Erectile Function-5. The MTHFR c.677C>T variant was also measured by fluorescence polymerase chain reaction (PCR). No significant difference in the genotypic frequency of the MTHFR C677T polymorphism (CC, CT, and TT) was observed between men from the ED and non-ED groups. In addition, on binary logistic regression analysis, both crude and adjusted models showed that the risk of ED was not significantly associated with the C677T polymorphism. Interestingly, a significantly higher frequency of the 677TT polymorphism was found in severe and moderate ED (P = 0.02). The positive correlation between the MTHFR 677TT polymorphism and severe ED was confirmed by logistic regression analysis, even after adjusting for potential confounders (odds ratio [OR] = 2.46, 95% confidence interval [CI]: 1.15-5.50, P = 0.02). These findings suggest a positive correlation between the MTHFR 677TT polymorphism and the risk of severe ED. Identification of MTHFR gene polymorphisms may provide complementary information for ED patients during routine clinical diagnosis.

Three-Dimensional Fully Conjugated Covalent Organic Frameworks for Efficient Photocatalytic Water Splitting.

Covalent organic frameworks (COFs) are promising photocatalysts for water splitting, but their efficiency lags behind that of inorganic counterparts partly due to the limited charge transport and optical absorption properties. To overcome this limitation, we proposed to employ three-dimensional (3D) fully conjugated (FC) COFs with a topological assembly of cyclooctatetraene derivatives for photocatalytic water splitting. On the basis of first-principles calculations, we demonstrated that these 3D FC-COFs are semiconductors with exceptional charge transport and optical absorption properties. The carrier mobilities are comparable to those of inorganic semiconductors and superior to the record mobility observed in two-dimensional COFs. Additionally, the 3D FC-COFs exhibit broad visible light absorption with direct band gaps and high optical absorption coefficients. Among them, two 3D FC-COFs are identified for overall water splitting, while three others can facilitate the hydrogen evolution half-reaction. This study pioneers the design of 3D FC-COF photocatalysts, potentially advancing their applications in photocatalysis and optoelectronics.

A Data-Driven Search of Two-Dimensional Covalent Organic Frameworks for Visible-Light-Driven Overall Water Splitting.

Two-dimensional (2D) covalent organic frameworks (COFs) with versatile structural and optoelectronic properties that can be tuned with building blocks and topological structures have received widespread attention for photocatalytic water splitting in recent years. However, few of these have been reported for overall water splitting under visible light. Here, we present a data-driven search of 2D COFs capable of visible-light-driven overall water splitting by combining high-throughput first-principles computations and experimental validations. Seven 2D COFs were identified to be capable of overall water splitting from the CoRE COF database, and their photocatalytic activities were further verified and optimized by our preliminary experiments. The production rates of H2 and O2 reached 80 and 32 µmol g-1 h-1, respectively, without using sacrificial agents. This work represents an attempt to explore 2D COFs for visible-light-driven overall water splitting with a data-driven approach that could accelerate the discovery and design of COFs toward photocatalytic overall water splitting.

Band-Edge Prediction of 2D Covalent Organic Frameworks from Molecular Precursor via Machine Learning.

The band-edge positions of two-dimensional (2D) covalent organic frameworks (COFs) play a crucial role in their applications in photocatalysts and nanoelectronics. However, massive amounts of 2D COFs with targeted band-edge positions from high-level first-principles calculations based on their composition are time-consuming due to the diversity and complexity of unit cell structures. Here, we report a strategy to predict the band-edge positions of 2D COFs by combining first-principles calculations with machine learning (ML). The root-mean-square error (RMSE) of the predicted valence band maximum (VBM) and conduction band minimum (CBM) between ML prediction and first-principles calculated values at the Perdew-Burke-Ernzerhof (PBE) level are 0.229 and 0.247 eV in test data set, respectively. In addition, a linear relationship is established between the PBE results and the HSE06 results with RMSE values of 0.089 and 0.042 eV for VBMs and CBMs in the test data set. Finally, a workflow is developed to determine the band-edge positions of the 2D COFs.

Safety of early cumulus cell removal combined with early rescue ICSI in the prevention of fertilization failure.

RESEARCH QUESTION: What are the clinical outcomes and safety implications of early cumulus cell removal after short-term insemination combined with early rescue intracytoplasmic sperm injection (ICSI) in preventing fertilization failure? DESIGN: In this retrospective study, a total of 14,360 cycles were divided into four groups based on insemination method and fertilization ability: conventional IVF group (n = 5519); early cumulus cell removal group (n = 4107); conventional ICSI group (n = 4215); and early rescue ICSI group (where failed or low fertilization was predicted, n = 519). Fertilization outcomes, pregnancy outcomes, neonatal outcomes and birth defects were analysed by comparing the early cumulus cell removal group with the conventional IVF group, and the early rescue ICSI group with the conventional ICSI group. RESULTS: There were no significant differences in the outcomes of fertilization, pregnancy, neonates or birth defects between the conventional IVF group and the early cumulus cell removal group (P > 0.05). When compared with the conventional ICSI group, the early rescue ICSI group had similar rates of two pronuclei (2PN) at fertilization, clinical pregnancy, miscarriage, ectopic pregnancy, live birth, sex, mean gestational age, very low birthweight, macrosomia and birth defects (P > 0.05) but a higher polyploidy rate, lower high-quality embryo rate (both P < 0.001), lower twin pregnancy rate (P < 0.01), lower rate of low birthweight, and a higher rate of normal birthweight (both P = 0.024). CONCLUSIONS: Early cumulus cell removal combined with early rescue ICSI led to good pregnancy and neonatal outcomes without an increase in birth defects. This approach could therefore be an effective and safe method for patients with fertilization failure in conventional IVF.

Homozygous frameshift variant in POC1B causes male infertility with oligoasthenoteratozoospermia in human and mice.

Several different mutations in the proteome of centriole 1 centriolar protein B (POC1B) have been linked to cone dystrophy or cone-rod dystrophy (CORD). However, mutations in POC1B that are associated with both CORD and oligoasthenoteratozoospermia (OAT) have not been reported previously. Here, whole-exome sequencing was performed to identify a homozygous frameshift variant (c.151delG) in POC1B in the two brothers who had been diagnosed with both CORD and OAT from a consanguineous family. Transcript and protein analyses of biological samples from the two patients carrying the variant showed that POC1B protein is lost in sperm cells. The system CRISPR/Cas9 was utilized to create poc1bc.151delG/c.151delG knock-in (KI) mice. Notably, poc1bc.151delG/c.151delG KI male mice presented with OAT phenotype. Additionally, testicular histology and transmission electron microscopy analysis of the testes and sperm indicated that Poc1b mutation results in abnormal formation of acrosomes and flagella. Collectively, according to our experimental data on human volunteers and animal models, biallelic mutations in POC1B can cause OAT and CORD in mice and humans.

Association of BMI with erectile dysfunction: A cross-sectional study of men from an andrology clinic.

Abnormal body mass index (BMI) is associated with an increased risk of erectile dysfunction (ED). However, the relationship between different BMI categories and the levels of ED severity remains unclear. In the current study, 878 men from the andrology clinic in Central China were recruited. Erectile function was assessed by the International Index of Erectile Function (IIEF) scores. Questionnaires included questions about demographic characteristics (age, height, weight, educational status), lifestyle habits (drinking, smoking, sleep time), and medical history. Logistic regression was used to examine the association between ED risk and BMI. The incidence of ED was 53.1%. BMI was significantly higher in men from the ED group than in those from the non-ED group (P = 0.01). Compared with the normal weight group, obese men had a higher risk of ED (OR = 1.97, 95% CI = 1.25-3.14, P = 0.004), even after adjustment for potential confounders (OR = 1.78, 95% CI = 1.10-2.90, P = 0.02). Moreover, the positive correlation between obesity and moderate/severe ED severity was confirmed by logistic regression analysis (moderate/severe ED, OR = 2.71, 95% CI = 1.44-5.04, P = 0.002), even after adjusting for potential confounders (OR = 2.51 95% CI = 1.24-5.09, P = 0.01). Collectively, our findings indicate a positive correlation between obesity and the risk of moderate/severe ED. Clinicians could pay more attention to moderate/severe ED patients to maintain a healthy body weight to improve erectile function.

Biallelic mutations in WDR12 are associated with male infertility with tapered-head sperm.

Teratozoospermia is a rare disease associated with male infertility. Several recurrent genetic mutations have been reported to be associated with abnormal sperm morphology, but the genetic basis of tapered-head sperm is not well understood. In this study, whole-exome sequencing (WES) identified a homozygous WD repeat domain 12 (WDR12; p.Ser162Ala/c.484T>G) variant in an infertile patient with tapered-head spermatozoa from a consanguineous Chinese family. Bioinformatic analysis predicted this mutation to be a pathogenic variant. To verify the effect of this variant, we analyzed WDR12 protein expression in spermatozoa of the patient and a control individual, as well as in the 293T cell line, by Western blot analysis, and found that WDR12 expression was significantly downregulated. To understand the role of normal WDR12, we evaluated its mRNA and protein expression in mice at different ages. We observed that WDR12 expression was increased in pachytene spermatocytes, with intense staining visible in round spermatid nuclei. Based on these results, the data suggest that the rare biallelic pathogenic missense variant (p.Ser162Ala/c.484T>G) in the WDR12 gene is associated with tapered-head spermatozoa. In addition, after intracytoplasmic sperm injection (ICSI), a successful pregnancy was achieved. This finding indicates that infertility associated with this WDR12 homozygous mutation can be overcome by ICSI. The present results may provide novel insights into understanding the molecular mechanisms of male infertility.

Letrozole protects against cadmium-induced inhibition of spermatogenesis via LHCGR and Hsd3b6 to activate testosterone synthesis in mice.

The heavy metal cadmium is proposed to be one of the environmental endocrine disruptors of spermatogenesis. Cadmium-induced inhibition of spermatogenesis is associated with a hormone secretion disorder. Letrozole is an aromatase inhibitor that increases peripheral androgen levels and stimulates spermatogenesis. However, the potential protective effects of letrozole on cadmium-induced reproductive toxicity remain to be elucidated. In this study, male mice were administered CdCl2 (4 mg/kg BW) orally by gavage alone or in combination with letrozole (0.25 mg/kg BW) for 30 days. Cd exposure caused a significant decreases in body weight, sperm count, motility, vitality, and plasma testosterone levels. Histopathological changes revealed extensive vacuolization and decreased spermatozoa in the lumen. However, in the Cd + letrozole group, letrozole treatment compensated for deficits in sperm parameters (count, motility, and vitality) induced by Cd. Letrozole treatment significantly increased serum testosterone levels, which were reduced by Cd. Histopathological studies revealed a systematic array of all germ cells, a preserved basement membrane and relatively less vacuolization. For a mechanistic examination, RNA-seq was used to profile alterations in gene expression in response to letrozole. Compared with that in the Cd-treated group, RNA-Seq analysis showed that 214 genes were differentially expressed in the presence of letrozole. Gene ontology (GO) enrichment analysis and KEGG signaling pathway analysis showed that steroid biosynthetic processes were the processes most affected by letrozole treatment. Furthermore, we found that the expression of the testosterone synthesis-related genes LHCGR (luteinizing hormone/choriogonadotropin receptor) and Hsd3b6 (3 beta- and steroid delta-isomerase 6) was significantly downregulated in Cd-treated testes, but these genes maintained similar expression levels in letrozole-treated testes as those in the control group. However, the transcription levels of inflammatory cytokines, such as IL-1ß and IL-6, and oxidative stress-related genes (Nrf2, Nqo1, and Ho-1) showed no changes. The present study suggests that the potential protective effect of letrozole on Cd-induced reproductive toxicity might be mediated by the upregulation of LHCGR and Hsd3b6, which would beneficially increase testosterone synthesis to achieve optimum protection of sperm quality and spermatogenesis.

MBOAT1 homozygous missense variant causes nonobstructive azoospermia.

Nonobstructive azoospermia (NOA) is a common cause of infertility and is defined as the complete absence of sperm in ejaculation due to defective spermatogenesis. The aim of this study was to identify the genetic etiology of NOA in an infertile male from a Chinese consanguineous family. A homozygous missense variant of the membrane-bound O-acyltransferase domain-containing 1 (MBOAT1) gene (c.770C>T, p.Thr257Met) was found by whole-exome sequencing (WES). Bioinformatic analysis also showed that this variant was a pathogenic variant and that the amino acid residue in MBOAT1 was highly conserved in mammals. Quantitative polymerase chain reaction (Q-PCR) analysis showed that the mRNA level of MBOAT1 in the patient was 22.0% lower than that in his father. Furthermore, we screened variants of MBOAT1 in a broader population and found an additional homozygous variant of the MBOAT1 gene in 123 infertile men. Our data identified homozygous variants of the MBOAT1 gene associated with male infertility. This study will provide new insights for researchers to understand the molecular mechanisms of male infertility and will help clinicians make accurate diagnoses.

Association of paternal MTHFR polymorphisms (C677T) with clinical outcomes in ICSI treatment.

Purpose: This study aims to investigate the association between paternal methylenetetrahydrofolate reductase (MTHFR) polymorphisms (C677T) and embryonic development, pregnancy, and neonatal outcomes in intracytoplasmic sperm injection (ICSI) treatment. Methods: A total of 191 infertile men undergoing ICSI treatment at the Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, were recruited between January 2020 and June 2021. The MTHFR C677T polymorphism genotyping was evaluated in these male patients, and they were stratified into three groups according to genotyping results: Control (CC), heterozygote mutated (CT), and mutated homozygote (TT). In addition, we conducted a comparative analysis of embryonic development, pregnancy, and neonatal outcomes among these three groups. Results: The embryonic development (including normal fertilization rate (80.14% vs. 83.06% vs. 85.10%; p = 0.37), high-quality embryo rate (45.26% vs. 43.69% vs. 46.04%; p = 0.72), blastocyst formation rate (42.47% vs. 43.18% vs. 39.38%; p = 0.62), implantation rate (42.47% vs. 36.25% vs. 41.22%; p = 0.62), and clinical pregnancy rate (64.71% vs. 58.75% vs. 66.67%; p = 0.59) were not comparable among these three groups. Moreover, no significant difference was observed in terms of pregnancy outcomes (including miscarriage rate (24.24% vs. 12.77% vs. 22.5%; p = 0.35) and live birth rate (49.02% vs. 51.25% vs. 51.66%; p = 0.96)). Additionally, no marked difference was observed in terms of neonatal outcome (including, preterm delivery rate (24% vs. 14.63% vs. 9.67%; p = 0.35), birth height (p = 0.75), birth weight (p = 0.35), neonatal sex (p = 0.48), gestational age at delivery (p = 0.24), Apgar score (p = 0.34), and birth defects (0% vs. 2% vs. 9%; p = 0.23) among the study groups. Conclusion: The paternal MTHFR C677T polymorphism is not associated with embryo quality, pregnancy, or neonatal outcomes in ICSI treatment. Therefore, in our population, MTHFR polymorphisms do not provide helpful information in explaining ICSI failure.

Microwave frequency measurement with high accuracy and wide bandwidth based on whispering-gallery mode barcode.

We propose and experimentally demonstrate a novel method for photonic-assisted microwave frequency measurement based on whispering-gallery mode (WGM) barcode, which is a dense spectrum generated by a micro-resonator that supports a large number of optical modes. The measurement relies on the relation between the microwave frequency and its unique barcode. The proposed system has the advantages of wide bandwidth, high accuracy, and multiple-frequency measurement capability. Microwave frequency measurement from 1 to 20 GHz is experimentally demonstrated with a measurement error of 40 kHz. For multi-tone signals, the frequency resolution is demonstrated to be less than 20 MHz. A dynamic multi-tone microwave signal consists of a 16-20 GHz linear frequency-modulated (LFM) signal, and a 10 GHz signal is measured to show the capability of multiple-frequency measurement. The system stability is also evaluated, and a self-reference method is proposed to maintain a long-term high-accuracy measurement.

Sexually transmitted infections and semen quality from subfertile men with and without leukocytospermia.

BACKGROUND: The role of sexually transmitted infections (STIs) in semen parameters and male infertility is still a controversial area. Previous studies have found bacterial infection in a minority of infertile leukocytospermic males. This study aims to investigate the prevalence of STIs in semen from subfertile men with leukocytospermia (LCS) and without leukocytospermia (non-LCS) and their associations with sperm quality. METHODS: Semen samples were collected from 195 men who asked for a fertility evaluation. Infection with the above 6 pathogens was assessed in each sample. Sperm quality was compared in subfertile men with and without LCS. RESULTS: The LCS group had significantly decreased semen volume, sperm concentration, progressive motility, total motility and normal morphology. The infection rates of Ureaplasma urealyticum (Uuu), Ureaplasma parvum (Uup), Mycoplasma hominis (MH), Mycoplasma genitalium (MG), Chlamydia trachomatis (CT), herpes simplex virus-2 (HSV-2) and Neisseria gonorrhoeae (NG) were 8.7 %, 21.0 %, 8.2 %, 2.1 %, 3.6 %, 1.0 and 0 %, respectively. The STI detection rates of patients with LCS were higher than those of the non-LCS group (52.3 % vs. 39.3 %), although there was no statistically significant difference between the two groups (P = 0.07). All semen parameters were not significantly different between LCS with STIs and without STIs, except the semen volume in the MG-infected patients with LCS was significantly lower than that in the noninfected group. CONCLUSIONS: LCS was associated with a reduction in semen quality, but was not associated with STIs.

Semen parameters in men recovered from COVID-19.

The novel coronavirus disease (COVID-19) pandemic is emerging as a global health threat and shows a higher risk for men than women. Thus far, the studies on andrological consequences of COVID-19 are limited. To ascertain the consequences of COVID-19 on sperm parameters after recovery, we recruited 41 reproductive-aged male patients who had recovered from COVID-19, and analyzed their semen parameters and serum sex hormones at a median time of 56 days after hospital discharge. For longitudinal analysis, a second sampling was obtained from 22 of the 41 patients after a median time interval of 29 days from first sampling. Compared with controls who had not suffered from COVID-19, the total sperm count, sperm concentration, and percentages of motile and progressively motile spermatozoa in the patients were significantly lower at first sampling, while sperm vitality and morphology were not affected. The total sperm count, sperm concentration, and number of motile spermatozoa per ejaculate were significantly increased and the percentage of morphologically abnormal sperm was reduced at the second sampling compared with those at first in the 22 patients examined. Though there were higher prolactin and lower progesterone levels in patients at first sampling than those in controls, no significant alterations were detected for any sex hormones examined over time following COVID-19 recovery in the 22 patients. Although it should be interpreted carefully, these findings indicate an adverse but potentially reversible consequence of COVID-19 on sperm quality.

Rayleigh speckle-based wavemeter with high dynamic range and fast reference speckle establishment process assisted by optical frequency combs.

Compact speckle-based spectrometers that acquire lightwave wavelength from the speckle generated by turbid media are promising for high-resolution spectral analysis. For these devices, the reference establishment process is time consuming, and it is very difficult to obtain reference speckles covering a wide bandwidth with high resolution, which restricts the dynamic range in frequency (the ratio of bandwidth to resolution). In this Letter, we introduce optical frequency combs (OFCs) to the system to overcome these problems, which exist in the wavemeter based on Rayleigh speckle obtained from a single-mode fiber. In the experiment, the proposed wavemeter has a 1.5 nm bandwidth with 60 am resolution, covering a dynamic range in the frequency of 2×107, and a fast reference speckle establishment process that takes only 0.9 ms. The proposed method assisted by OFCs is a good prospect for a more practical speckle-based wavemeter with higher dynamic ranges.

A Simple and Efficient Method to Cryopreserve Human Ejaculated and Testicular Spermatozoa in -80°C Freezer.

Human autologous sperm freezing involves ejaculated sperm, and testicular or epididymal puncture sperm freezing, and autologous sperm freezing is widely used in assisted reproductive technology. In previous studies, researchers have tried to cryopreserve sperm from mammals (rats, dogs, etc.) using a -80°C freezer and have achieved success. It is common to use liquid nitrogen vapor rapid freezing to cryopreserve human autologous sperm. However, the operation of this cooling method is complicated, and the temperature drop is unstable. In this study, we compared the quality of human ejaculation and testicular sperm after liquid nitrogen vapor rapid freezing and -80°C freezing for the first time. By analyzing sperm quality parameters of 93 ejaculated sperm and 10 testicular sperm after liquid nitrogen vapor rapid freezing and -80°C freezing, we found reactive oxygen species (ROS) of sperm of the -80°C freezer was significantly lower than liquid nitrogen vapor rapid freezing. Regression analysis showed that progressive motility, ROS, and DNA fragmentation index (DFI) in post-thaw spermatozoa were correlated with sperm progressive motility, ROS, and DFI before freezing. For the freezing method, the -80°C freezer was positively correlated with the sperm progressive motility. Among the factors of freezing time, long-term freezing was negatively correlated with sperm progressive motility and ROS. Although freezing directly at -80°C freezer had a slower temperature drop than liquid nitrogen vapor rapid freezing over the same period, the curves of the temperature drop were similar, and slight differences in the freezing point were observed. Furthermore, there were no statistically significant differences between the two methods for freezing testicular sperm. The method of direct -80°C freezing could be considered a simplified alternative to vapor freezing for short-term human sperm storage. It could be used for cryopreservation of autologous sperm (especially testicular sperm) by in vitro fertilization centers. Clinical Trial Registration: (website), identifier (ChiCTR2100050190).

Association of Alcohol Intake and Semen Parameters in Men With Primary and Secondary Infertility: A Cross-Sectional Study.

Alcohol consumption has commonly been associated with semen parameters. However, the association between alcohol intake and semen parameters in primary and secondary infertile men remains unclear. In this study, 776 infertile men from China were grouped according to alcohol intake: abstainers, moderate drinkers (<9 units/week, up to approximately 100 g of ethanol) and heavy drinkers (≥9 units/week). Semen parameters, including semen volume, sperm concentration, total sperm count, progressive motility and normal morphology were investigated. Alcohol consumption and other lifestyle factors were assessed by questionnaire. Logistic regression models were applied. There was no significant association between alcohol consumption and semen parameters in men with primary infertility. Smaller testis volumes and lower sperm concentrations were found among moderate and heavy drinkers in the secondary infertility group than among abstainers. After adjustment for potential confounders, men with secondary infertility and heavy alcohol consumption had a higher risk of abnormal sperm concentrations (OR = 3.72; 95% CI, 1.04, 13.37). These findings suggest that alcohol intake may decrease sperm concentrations in men with secondary infertility, whereas no association was found in men with primary infertility. It may be beneficial for clinicians to advise male patients with secondary infertility who are seeking fertility treatment to avoid heavy alcohol consumption.