Effects of low doses of cyproterone acetate on sperm morphology and some other parameters of reproduction in normal men

Influence of circulating testosterone concentration on sperm cryoresistance: The ibex as an experimental model

BACKGROUND

Recent studies have noted that the circulating testosterone concentration may affect the ability of spermatozoa to survive cryopreservation. However, few attempts to confirm such a relationship have been made. Wild ruminant species have very marked seasonal changes in their reproductive function and strong annual changes in their plasma testosterone concentration.

OBJECTIVES

The present work examines the influence of induced changes in testosterone secretion on sperm variables following conventional slow freezing and ultra-rapid freezing, using the Iberian ibex as an experimental model.

MATERIALS AND METHODS

In a first experiment, testosterone levels were reduced in the middle of the rutting season (December) using the antiandrogen cyproterone acetate (CA). In a second experiment, testosterone levels were increased at the end of the rutting season (January) via the use of the androgen testosterone propionate (TP).

RESULTS

During December, the testosterone concentration was found to be higher in the blood and seminal plasma of untreated males than in those of CA-treated males (p < 0.001 and p < 0.05, respectively). Compared with controls, the TP-treated animals had higher blood plasma testosterone concentrations but lower seminal plasma testosterone concentrations during January (p < 0.01 and p < 0.001, respectively). The seminal vesicles of the TP-treated males were larger than those of untreated males (p < 0.05). When CA was administered, sperm viability improved compared with controls (p < 0.05), irrespective of the freezing protocol followed. For the ultra-rapid freezing procedure, the cryoresistance ratio for motility decreased when TP was administered (p < 0.05). The values for fresh sperm morphometric variables decreased during the 50 days after the end of CA treatment (p < 0.001) and increased over the same time after the end of TP treatment (p < 0.001).

DISCUSSION AND CONCLUSION

The circulating testosterone concentration appears to influence sperm cryoresistance. This may explain the seasonal changes seen in sperm freezability in some species, independent of fresh sperm quality.

Fertility preservation options in transgender people: A review

Gender affirming procedures adversely affect the reproductive potential of transgender people. Thus, fertility preservation options should be discussed with all transpeople before medical and surgical transition. In transwomen, semen cryopreservation is typically straightforward and widely available at fertility centers. The optimal number of vials frozen depends on their reproductive goals and treatment options, therefore a consultation with a fertility specialist is optimal. Experimental techniques including spermatogonium stem cells (SSC) and testicular tissue preservation are technologies currently under development in prepubertal individuals but are not yet clinically available. In transmen, embryo and/or oocyte cryopreservation is currently the best option for fertility preservation. Embryo cryopreservation requires fertilization of the transman's oocytes with a donor or partner's sperm prior to cryopreservation, but this limits his future options for fertilizing the eggs with another partner or donor. Oocyte cryopreservation offers transmen the opportunity to preserve their fertility without committing to a male partner or sperm donor at the time of cryopreservation. Both techniques however require at least a two-week treatment course, egg retrieval under sedation and considerable cost. Ovarian tissue cryopreservation is a promising experimental method that may be performed at the same time as gender affirming surgery but is offered in only a limited amount of centers worldwide. In select places, this method may be considered for prepubertal children, adolescents, and adults when ovarian stimulation is not possible. Novel methods such as in-vitro activation of primordial follicles, in vitro maturation of immature oocytes and artificial gametes are under development and may hold promise for the future.

Update on male hormonal contraception: is the vasectomy in jeopardy?

Traditionally, male contraception has consisted of either barrier methods, such as condoms, or vasectomy. However, in recent years, we have made great strides in the basic science and clinical medicine to better understand the feedback mechanisms and physiology of the male reproductive system. These advances have enabled the development of several nonsurgical, hormonal, reversible, well-tolerated alternatives for male contraception. Men are more likely now than ever to participate in the choice of contraceptive techniques. This review will discuss the current status and recent developments in nonsurgical hormonal male contraception, a field that has been historically limited by social, financial and physiological challenges.

Effects of cyproterone acetate with combination of testosterone enanthate on seminal characteristics, androgenicity and clinical chemistry in langur monkey

Daily oral administration of 1 mg/kg b.w. of cyproterone acetate and simultaneously administered testosterone enanthate (2 mg/kg b.w./15 days; i.m.) to adult male langur monkeys over a period of 90 days caused a gradual decrease in the count (to azoospermia) and motility of spermatozoa, concurrently with an increase in the percentage of non-motile as well as abnormal and immature sperm. Semen weight, volume, seminal fluid volume and circulating testosterone levels decreased nonsignificantly. Semen pH, libido and body weight remained unimpaired. The levels of SGOT, SGPT, serum alkaline phosphatase, LDH, bilirubin, Na+, K+ and hematological values did not alter significantly. All the changes were reversible. The results indicate that the combination regimen seems to affect the fertility in two ways, i.e. by inhibiting spermatogenesis in the testis and maturation process in the epididymis without altering the androgenicity.