In 1992 a worldwide decline in sperm density was reported; this was quickly followed by numerous critiques and editorials. Because of the public health importance of this finding, a detailed reanalysis of data from 61 studies was warranted to resolve these issues. Multiple linear regression models (controlling for abstinence time, age, percent proven fertility, specimen collection method, study...

Bone morphogenetic protein 15 (BMP-15) expression has been detected in the testis, but its roles in this organ has not been well elucidated. We evaluated polymorphisms of the BMP-15 gene by PCR-SSCP and PCR-RFLP in 212 Chinese Holstein bulls, and investigated possible associations with sperm quality traits, including semen volume per ejaculate, sperm density, fresh sperm motility, thawed sperm ...

Background: At least 50% of infertile couple's problems are related to male factor infertility and in many patients; nutritional problems have been related to decreased sperm quality. Thus, the present study aims to examine the association of dietary fat and mineral intake with semen quantity and quality. Methods: This cross-sectional study was conducted on 175 infertile men in Isfahan Infertil...

Background Chromomycin A3 (CMA3) staining has been used to assess protamine deficiency. The aim of this study was to determine credibility of CMA3 along with semen parameters for assessment of fertility potential. MaterialsAndMethods Semen analysis and CMA3 staining were carried out on 234 fertile and 178 subfertile individuals. Semen analysis was assessed according to WHO criteria. Protamine d...

The acrosome is a large secretory vesicle of the sperm head that carries enzymes responsible for the digestion of the oocyte's investments. The event leads to sperm penetration and allows fertilization to occur. Release of the acrosomal enzymes is mediated by the interaction between sperm acrosomal and plasma membranes (acrosome reaction). Biochemical characterization of the acrosomal membrane ...

background: chromomycin a3 (cma3) staining has been used to assess protamine deficiency. the aim of this study was to determine credibility of cma3 along with semen parameters for assessment of fertility potential. materials and methods: semen analysis and cma3 staining were carried out on 234 fertile and 178 subfertile individuals. semen analysis was assessed according to who criteria. protami...

Gamete recognition proteins can evolve at astonishing rates and lie at the heart of reproductive isolation and speciation in diverse taxa. However, the source of selection driving this evolution remains unknown. We report on how the sperm bindin genotype influences reproductive success under natural conditions. An interaction between genotype frequency and spawning density determines how sperm ...

OBJECTIVE To determine the effect of semen storage and separation techniques on sperm DNA fragmentation. DESIGN Controlled clinical study. SETTING An assisted reproductive technology laboratory. PATIENT(S) Thirty normoozospermic semen samples obtained from patients undergoing infertility evaluation. INTERVENTION(S) One aliquot from each sample was immediately prepared (control) for the ...

Background: Telomeres are particular sequences of DNA located at the end of the eukaryotic chromosomes that are essential for genome integrity. Telomere length in spermatozoa differs among males, as well as spermatozoa. Also, decreased telomere length in spermatozoa of infertile men is associated with the reduction of fertility potential and embryo quality. Density gradient centrifugation (DGC)...

Postcopulatory sexual selection is widely accepted to underlie the extraordinary diversification of sperm morphology. However, why does it favour longer sperm in some taxa but shorter in others? Two recent hypotheses addressing this discrepancy offered contradictory explanations. Under the sperm dilution hypothesis, selection via sperm density in the female reproductive tract favours more but s...