OBJECTIVE: To explore the incidence of azoospermia factor c (AZFc) microdeletion among patients with azoospermia or severe oligospermia, its association with sex hormone/chromosomal karyotype, and its effect on the outcome of pregnancy following intracytoplasmic sperm injection (ICSI) treatment. METHODS: A total of 1 364 males with azoospermia or severe oligospermia who presented at the Affiliated Maternity and Child Health Care Hospital of Jiaxing College between 2013 and 2020 were subjected to AZF microdeletion and chromosome karyotyping analysis. The level of reproductive hormones in patients with AZFc deletions was compared with those of control groups A (with normal sperm indices) and B (azoospermia or severe oligospermia without AZFc microdeletion). The outcome of pregnancies for the AZFc-ICSI couples was compared with that of the control groups in regard to fertilization rate, superior embryo rate and clinical pregnancy rate. RESULTS: A total of 51 patients were found to harbor AZFc microdeletion, which yielded a detection rate of 3.74%. Seven patients also had chromosomal aberrations. Compared with control group A, patients with AZFc deletion had higher levels of PRL, FSH and LH (P < 0.05), whilst compared with control group B, only the PRL and FSH were increased (P < 0.05). Twenty two AZFc couples underwent ICSI treatment, and no significant difference was found in the rate of superior embryos and clinical pregnancy between the AZFc-ICSI couples and the control group (P > 0.05). CONCLUSION The incidence of AZFc microdeletion was 3.74% among patients with azoospermia or severe oligospermia. AZFc microdeletion was associated with chromosomal aberrations and increased levels of PRL, FSH and LH, but did not affect the clinical pregnancy rate after ICSI treatment.
Child ; Humans ; Male ; Female ; Pregnancy ; Azoospermia/genetics* ; Oligospermia/genetics* ; Incidence ; Chromosome Deletion ; Chromosomes, Human, Y/genetics* ; Semen ; Infertility, Male/genetics* ; Chromosome Aberrations ; Follicle Stimulating Hormone/genetics*

Mycoplasma species (spp.) are bacteria that are difficult to detect. Currently, the polymerase chain reaction (PCR) is considered the most effective diagnostic tool to detect these microorganisms in both human and veterinary medicine. There are 13 known species of human Mycoplasma and 15 species of canine Mycoplasma. Owing to the difficulties in identifying the individual species of Mycoplasma, there is a lack of information regarding which species are saprophytic and which are pathogenic. The prevalence of the individual species is also unknown. In addition, in both humans and dogs, the results of some studies on the impact of Mycoplasma are conflicting. The presence of Mycoplasma spp. on the epithelium of reproductive tract is often associated with infertility, although they are also detected in healthy individuals. The occurrence of Mycoplasma spp. is more common in dogs (even 89%) than in humans (1.3%-4%). This is probably because the pH of a dog's genital is more conducive to the growth of Mycoplasma spp. than that of humans. Phylogenetically, human and canine Mycoplasma are related, and majority of them belong to the same taxonomic group. Furthermore, 40% of canine Mycoplasma spp. are placed in common clusters with those of human. This suggests that species from the same cluster can play a similar role in the canine and human reproductive tracts. This review summarizes the current state of knowledge about the impact of Mycoplasma on canine and human male fertility as well as the prospects of further development in this field.
Humans ; Dogs ; Male ; Animals ; Mycoplasma/genetics* ; Infertility ; Semen Analysis ; Polymerase Chain Reaction/methods* ; Prevalence ; Semen/chemistry*

Spermatogenesis is regulated by several Y chromosome-specific genes located in a specific region of the long arm of the Y chromosome, the azoospermia factor region (AZF). AZF microdeletions are the main structural chromosomal abnormalities that cause male infertility. Assisted reproductive technology (ART) has been used to overcome natural fertilization barriers, allowing infertile couples to have children. However, these techniques increase the risk of vertical transmission of genetic defects. Despite widespread awareness of AZF microdeletions, the occurrence of de novo deletions and overexpression, as well as the expansion of AZF microdeletion vertical transmission, remains unknown. This review summarizes the mechanism of AZF microdeletion and the function of the candidate genes in the AZF region and their corresponding clinical phenotypes. Moreover, vertical transmission cases of AZF microdeletions, the impact of vertical inheritance on male fertility, and the prospective direction of research in this field are also outlined.
Humans ; Male ; Azoospermia/genetics* ; Sex Chromosome Aberrations ; Prospective Studies ; Chromosome Deletion ; Chromosomes, Human, Y/genetics* ; Infertility, Male/genetics* ; Sertoli Cell-Only Syndrome/genetics* ; Oligospermia/genetics*

In this review, we tried to systematize all the evidence (from PubMed [MEDLINE], Scopus, Cochrane Library, EBSCO, Embase, and Google Scholar) from 1993 to 2021 on the predictors of microsurgical varicocelectomy efficacy in male infertility treatment. Regarding the outcomes of varicocele repair, we considered semen improvement and pregnancy and analyzed them separately. Based on the 2011 Oxford CEBM Levels of Evidence, we assigned a score to each trial that studied the role of the predictor. We systematized the studied predictors based on the total points, which were, in turn, calculated based on the number and quality of studies that confirmed or rejected the studied predictor as significant, into three levels of significance: predictors of high, moderate, and low clinical significance. Preoperative total motile sperm count (TMSC) coupled with sperm concentration can be a significant predictor of semen improvement and pregnancy after varicocelectomy. In addition, for semen improvement alone, scrotal Doppler ultrasound (DUS) parameters, sperm DNA fragmentation index (DFI), and bilateral varicocelectomy are reliable predictors of microsurgical varicocelectomy efficacy.
Female ; Humans ; Male ; Pregnancy ; Infertility, Male/surgery* ; Microsurgery ; Semen ; Sperm Count ; Sperm Motility ; Varicocele/surgery*

Infertility has become a serious disease since it affects 10%-15% of couples worldwide, and male infertility contributes to about 50% of the cases. Notably, a significant decrease occurs in the newborn population by 7.82 million in 2020 compared to 2016 in China. As such, it is essential to explore the effective methods of obtaining functional male gametes for restoring male fertility. Stem cells, including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), spermatogonial stem cells (SSCs), and mesenchymal stem cells (MSCs), possess the abilities of both self-renewal and differentiation into germ cells. Significantly, much progress has recently been achieved in the generation of male germ cells in vitro from various kinds of stem cells under the specified conditions, e.g., the coculturing with Sertoli cells, three-dimensional culture system, the addition of growth factors and cytokines, and/or the overexpression of germ cell-related genes. In this review, we address the current advance in the derivation of male germ cells in vitro from stem cells based on the studies of the peers and us, and we highlight the perspectives and potential application of stem cell-derived male gametes in reproductive medicine.
Humans ; Infant, Newborn ; Male ; Germ Cells ; Embryonic Stem Cells ; Cell Differentiation ; Infertility, Male ; Induced Pluripotent Stem Cells

The authors performed a comprehensive review of current literature to create a model comparing commonly evaluated variables in male factor infertility, for example, follicle-stimulating hormone (FSH), testicular volume (TV), and testosterone (T), to better predict sperm retrieval rate (SRR). Twenty-nine studies were included, 9 with data on conventional testicular sperm extraction (cTESE) for a total of 1227 patients and 20 studies including data on microdissection testicular sperm extraction (mTESE) for a total of 4760 patients. A weighted-means value of SRR, FSH, T, and TV was created, and a weighted linear regression was then used to describe associations among SRR, type of procedure, FSH, T, and TV. In this study, weighted-means values demonstrated mTESE to be superior to cTESE with an SRR of 51.9% vs 40.1%. Multiple weighted linear regressions were created to describe associations among SRR, procedure type, FSH, T, and TV. The models showed that for every 1.19 mIU ml^-1 increase in FSH, there would be a significant decrease in SRR by 1.0%. Seeking to create a more clinically relevant model, FSH values were then divided into normal, moderate elevation, and significant elevation categories (FSH <10 mIU ml^-1, 10-19 mIU ml^-1, and >20 mIU ml^-1, respectively). For an index patient undergoing cTESE, the retrieval rates would be 57.1%, 44.3%, and 31.2% for values normal, moderately elevated, and significantly elevated, respectively. In conclusion, in a large meta-analysis, mTESE was shown to be more successful than cTESE for sperm retrievals. FSH has an inverse relationship to SRR in retrieval techniques and can alone be predictive of cTESE SRR.
Humans ; Male ; Follicle Stimulating Hormone ; Follicle Stimulating Hormone, Human ; Infertility, Male ; Linear Models ; Semen ; Sperm Retrieval ; Spermatozoa ; Testis/surgery*

Congenital bilateral absence of the vas deferens (CBAVD) is observed in 1%-2% of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. CFTR is one of the most well-known genes related to male fertility. The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia (NOA). CFTR mutations are highly polymorphic and have established ethnic specificity. Compared with F508Del in Caucasians, the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis. However, whether p.G970D participates in male infertility remains unknown. Herein, a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA. Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation (4.1%, 5/122), excluding polymorphic sites. Furthermore, we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients. The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells. In spermatocyte GC-2(spd)ts (GC2) Cftr p.G965D cells, RNA splicing variants were detected and CFTR expression decreased, which may contribute to the phenotypes associated with impaired spermatogenesis. Thus, this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.
Humans ; Animals ; Mice ; Male ; Mutation, Missense ; Retrospective Studies ; Cystic Fibrosis Transmembrane Conductance Regulator/genetics* ; Infertility, Male/genetics* ; Mutation ; Vas Deferens/abnormalities* ; Spermatogenesis/genetics*

Wenzhou has improved its environmental quality because of comprehensive environmental remediation; nevertheless, the semen quality of infertile males remains unclear. This study determined whether better environmental quality improved semen quality in this region. We recorded semen quality data from 22 962 infertile males from January 2014 to November 2019 at the Center for Reproductive Health of The First Affiliated Hospital of Wenzhou Medical University (Wenzhou, China). Patients were predominantly 30-35 years old (33.1%) and workers (82.0%), with high school education or lower (77.6%); more than a half of the patients (52.6%) were Wenzhou household registration; and most patients (77.5%) had abnormal semen quality. Patients who were older than 40 years and workers, and those with Wenzhou household registration, had significantly worse semen quality (all P < 0.05). From 2014 to 2019, progressive sperm motility, total sperm motility, and semen volume showed increasing linear trends in all patients (P = 0.021, 0.030, and 0.005, respectively), yet normal sperm morphology showed a linearly decreasing trend (P = 0.046). Sensitivity analyses for subgroups yielded similar results. In conclusion, the improvement of environmental quality and better function of the accessory glands are associated with progressive sperm motility, total sperm motility, and semen volume. Normal sperm morphology is influenced by occupational exposures and personal lifestyle and does not improve with environmental quality.
Male ; Humans ; Adult ; Semen Analysis ; Semen ; Sperm Count ; Sperm Motility ; Infertility, Male ; Spermatozoa

Male ; Humans ; Semen Analysis ; Semen ; Infertility, Male

The hemodynamic characteristics of venous reflux are associated with infertility in patients with varicocele; however, an effective method for quantifying the structural distribution of the reflux is lacking. This study aimed to predict surgical outcomes using a new software for venous reflux quantification. This was a retrospective cohort study of a consecutive series of 105 patients (age range: 22-44 years) between July 2017 and September 2019. Venous reflux of the varicocele was obtained using the Valsalva maneuver during scrotal Doppler ultrasonography before microsurgical varicocelectomy. Using this software, the colored reflux signals were segmented, and the gray scale of the color pixels representing the reflux velocity was comprehensively quantified into the mean reflux velocity of the green layer (MRVG) and the reflux velocity standard deviation of the green layer (RVSDG). Spontaneous pregnancy and changes from baseline in the semen parameters were assessed during a 12-month follow-up period. Data were analyzed using logistic regression analysis. An association of the high MRVG group with impaired progressive motility (odds ratio [OR] = 2.868, 95% confidence interval [CI]: 1.133-7.265) and impaired sperm concentration (OR = 2.943, 95% CI: 1.196-7.239) was found during multivariate analysis. High MRVG (OR = 2.680, 95% CI: 1.086-6.614) and high RVSDG (OR = 2.508, 95% CI: 1.030-6.111) were found to be independent predictors of failure to achieve pregnancy following microsurgical repair. In summary, intense venous reflux is an independent predictor of impaired progressive motility, sperm concentration, and pregnancy outcomes after microsurgical varicocelectomy.
Pregnancy ; Female ; Humans ; Male ; Young Adult ; Adult ; Varicocele/surgery* ; Retrospective Studies ; Semen ; Veins/surgery* ; Sperm Count ; Infertility, Male/surgery* ; Microsurgery/methods* ; Sperm Motility