Effect of Sperm Morphology in Intrauterine Insemination: Analysis of 115 Cycles and Literature Review.

IMPORTANCE: The value of morphology as a sperm parameter remains uncertain. Many studies have addressed the importance of morphology to predict the success of intrauterine insemination (IUI), but with conflicting results. OBJECTIVE: The aims of this study were to review the current literature, to query our own clinical experience via a retrospective, descriptive study, and to determine whether the diagnosis of isolated teratozoospermia influences pregnancy rate after IUI. RESULTS: We identified a large number of studies addressing this question. All were retrospective and most used different criteria to assess sperm morphology. Further complicating matters, the cutoff for normal morphology decreased from 15% to 4%. In our patient population, we found 12 cases of isolated teratozoospermia (10.43%). Only one of these produced an ongoing pregnancy and live birth. In all other cases, alteration of other sperm parameters coexisted (89.57%). These cycles produced a pregnancy rate of 13%, a nonsignficant difference. Pregnancy rates also were analyzed according to the percentage of normal morphology: 35.71% for less than 4%, 50% for 5% to 9%, and 14.29% for 10% to 14%. These rates did not differ significantly. CONCLUSIONS AND RELEVANCE: No consistent effect of sperm morphology on pregnancy rate was found in either the published literature or our own clinical experience. Larger and prospective studies are needed to identify any subtle effects of morphology on IUI outcomes that might exist.

Deletion of dpy-19 like 2 (DPY19L2) gene is associated with total but not partial globozoospermia.

The dpy-19 like 2 (DPY19L2) gene is the most common genetic cause of globozoospermia characterised by the production of round-headed spermatozoa without an acrosome. The present study was performed on 63 men with globozoospermia and 41 normozoospermic individuals to evaluate the frequency of the DPY19L2 gene and exons; deletion and genetic changes in exons 1, 5, 7-11, 19, 21 and interval introns; and some epidemiological factors (e.g. varicocele, smoking, drug use, alcohol consumption and a family history of infertility). Homozygous deletion of DPY19L2 was identified in 35% of men with globozoospermia. Exon 7 was deleted in 4.8% of men with globozoospermia in which DPY19L2 was not deleted. No genetic variations were observed within the DPY19L2 exons examined, but five intronic polymorphisms were detected: 1054-77T>C in intron 9, 1131+65T>C and 1131+53A>G in intron 10 and 1218+22T>C and 1218+73T>C in intron 11. There were significant differences in the frequency of 1054-77T>C and 1218+22T>C polymorphisms between the globozoospermic and normozoospermic groups. In addition, there were significant differences between the two groups in sperm count, sperm motility, a history of infertility in the family and varicocele. Based on these findings, DPY19L2 deletion is the major cause of total globozoospermia and there is no association between exons 1, 5, 8-11, 19 and 21 polymorphisms of the DPY19L2 gene in the occurrence of this defect.

Recategorisation of body mass index to achieve andrological predictive power: a study in more than 20 000 patients.

The aim of this study was to recategorise body mass index (BMI) in order to classify patients according to their risk of semen abnormalities. Patients (n=20563) presenting at an andrology laboratory were classified into five groups according to BMI: underweight (BMI <20kg m-2), normal weight (BMI 20-24.9kg m-2), overweight (BMI 25-29.9kg m-2), obese (BMI 30-39.9kg m-2) and morbidly obese (BMI >40kg m-2). Semen quality was evaluated to determine: (1) differences between groups using analysis of variance (ANOVA); (2) the chances of semen abnormalities (using generalised linear models, Chi-squared tests and odds ratios); (3) reference BMI values with andrological predictive power (multivariate conglomerate analyses and multivariate analysis of variance (MANOVA)); and (4) expected values of abnormalities for each new group resulting from BMI recategorisation. Morbidly obese and underweight patients exhibited the highest decrease in semen quality and had higher chances of semen abnormalities. The smallest number of sperm abnormalities was found at a BMI of 27kg m-2. Four reference values were identified, recategorising BMI into four groups according to their risk of semen abnormalities (from lowest to highest risk): Group1,BMI between 20 and 32kg m-2; Group2, BMI <20 and BMI >32-37kg m-2; Group3, BMI >37-42kg m-2; and Group4, BMI >42kg m-2. A BMI <20 or >32kg m-2 is negatively associated with semen quality; these negative associations on semen quality increase from a BMI >37kg m-2 and increase even further for BMI >42kg m-2. The BMI recategorisation in this study has andrological predictive power.

Single-nucleotide polymorphism c.474G>A in the SEPT12 gene is a predisposing factor in male infertility.

SEPT12 is a testis-specific gene involved in the terminal differentiation of male germ cells. SEPT12 protein is required for sperm head-tail formation and acts as a fundamental constituent of sperm tail annulus. In this study, we screened genetic variations in exons 5, 6, 7 of the SEPT12 and assessed the annulus status in teratozoospermic, globozoospermic, and patients with immotile short tail sperm. DNA sequencing was performed for 90 teratozoospermic and 30 normozoospermic individuals. Immunocytochemistry, transmission electron microscopy and western blotting were conducted to evaluate annulus status and the expression level of SEPT12 in patients with a distinct exonic variation (c.474G>A), respectively. Five polymorphisms identified within the desired regions of the SEPT12, among them c.474G>A had the potential to induce aberrant splicing results in the expression of a truncated protein. The annulus was detected in most of the spermatozoa from teratozoospermic and normozoospermic men with c.474G>A. In contrast, in the patient with short tail sperm defect carrying c.474G>A, 99% of spermatozoa were devoid of the annulus. Based on our findings there would be no association between exons 5, 6, 7 polymorphisms of the SEPT12 gene and the occurrence of mentioned disease but c.474G>A would be a predisposing factor in male infertility.

Transmission electron microscopy analysis of the origin and incidence of sperm intranuclear cytoplasmic retention in fertile and teratozoospermia men.

The human sperm nucleus contains cytoplasm. However, the origin and incidence of human sperm intranuclear cytoplasmic retention (INCR) remain unknown. The objectives of this study were to observe the morphological origin of INCR within the seminiferous epithelium and investigate the incidence of INCR in fertile and teratozoospermia men using transmission electron microscopy (TEM). By TEM, INCR initially appeared in elongating round spermatid nuclei and varied in size, number, shape, content, location and distribution within sperm nuclei. The teratozoospermia group (n = 16) demonstrated a higher incidence of INCR than did the fertile group (n = 16) (17.6 ± 5.2% vs. 9.7 ± 3.4%; p = 0.000). In the fertile group, no correlations were found between the incidence of INCR and abnormal sperm morphology, nuclear vacuole, acrosome integrity, motility or concentration (p > 0.05). However, the incidence of INCR exhibited a positive relationship with sperm abnormal morphology in the teratozoospermia group (r = 0.616, p = 0.011). These results demonstrate that INCR occurs in the early process of spermatogenesis and is an alteration found in the nucleus. Spermatozoa from teratozoospermia men contained more INCRs than those from fertile males. More attention should be paid to the possibility of spermatozoa containing INCR when using spermatozoa with abnormal head morphology for clinical or diagnostic purposes.

DNAH1 gene mutations and their potential association with dysplasia of the sperm fibrous sheath and infertility in the Han Chinese population.

OBJECTIVE: To investigate dynein, axonemal, heavy chain 1 (DNAH1) gene mutations that may be associated with dysplasia of the sperm fibrous sheath (DFS) and infertility in the Han Chinese population. DESIGN: Dysfunction of DNAH1 is known to cause multiple morphologic abnormalities of the flagella (MMAF), DFS, and infertility. Whole-exome sequencing was performed in DFS subjects and the healthy control subjects. SETTING: Not applicable. PATIENT(S): Twenty-one patients of Han ethnicity with primary infertility and diagnosed with asthenozoospermia and MMAF, but without primary ciliary dyskinesia. Fifty healthy men with normal fertility served as control subjects. MAIN OUTCOME MEASURE(S): Whole-exome sequencing, polymerase chain reaction and sequencing, pedigree analysis, Western blotting, and immunofluorescence assay. INTERVENTIONS(S): None. RESULT(S): A total of 17 mutations in the DNAH1 gene were identified in 12 of the 21 patients. These included one homozygous mutation at the splice site and 16 complex heterozygous mutations at the splice sites and exons. These mutations may cause deletion, replacement of amino acids in the peptide, or introduction of a stop codon in the coding sequence according to bioinformatic prediction. Of note, 52430998CCT>C deletion at exon 73, which may result in c.11726_11727del:p.P3909fs, was found in six patients, which suggests that this mutation may be an etiologic factor for MMAF. Although these DNAH1 gene mutations were found in Exome Aggregation Consortium (ExAC) databases, none were found in the Han healthy control subjects. The expression of DNAH1 protein in the sperm of patient P10, with 52409336C>T in exon 45 and 52430998CCT>C in exon 73 mutations, and patient P12, with 52402755A>G in exon 37 and 52428484G>T in exon 67 mutations, was missing or very weak compared with the sperm of healthy control subjects. The peptide phenotypes of 52409336C>T, 52402755A>G, and 52428484G>T were R2356W, nonsense, and E3544X, respectively. The sperm tails were short or coiled in P10 and P12 compared with healthy control subjects. Pedigree analysis supported the notion that the combination of DNAH1 gene mutations 52430998CCT>C and 52409336C>T and 52428484G>T alone were associated with MMAF. CONCLUSION(S): These DNAH1 gene mutations may be associated with DFS and infertility in the Han population.