Study On Cryopreservation Of Human Low-quality Semen

Human low-quality semen is a pathological semen, which has low semen routine parameters, characteristics and/or poor sperm functions. During cryopreservation, sperm undergo dramatic changes in intracellular and extracellutar environments due to exposure to cryoprotants, cooling, freezing, storing in liquid nitrogen, and thawing. The chemical and physical effects of these processes may cause extensive cryodamage to sperm membranes that can greatly influence sperm functions for human low-quality semen. Therefore, studying on cryopreservation of human low-quality semen can not only understand changes of frozen-thawed sperm functions, but also promote the application of frozen-thawed low-quality semen.The present investigation was carried out to evaluate the cryopreservation of four types of low-quality semen, which were from varicocele men, hematospermic men, globozoospermic men, and men with sperm immunological infertility, respectively. These four types semen were selected and divided according to their pathological reasons. For each type of the low-quality semen, the study focused on: (1) analyzing the cryobiological characteristics of frozen thawed sperm; (2) comparing different cryopreservation or treatment techniques; and (3) observing the application of frozen-thawed sperm by using artificial insemination. The obtained results are as follows.For cryopreservation of semen from men with varicocele, the results showed that: (1) all parameters including motility, membrane integrity rate of HOS-EY test survival time in vitro, cervical mucus penetration ability of SMMPT, acrosomal proteinase activity of frozen-thawed sperm were significantly lowered as compared with those of fresh sperm (P<0.01); (2) the characteristic of...