Endocrine approaches to male fertility control

Comprehensive review on the positive and negative effects of various important regulators on male spermatogenesis and fertility

With the increasing global incidence of infertility, the influence of environmental factors, lifestyle habits, and nutrients on reproductive health has gradually attracted the attention of researchers. The quantity and quality of sperm play vital roles in male fertility, and both characteristics can be affected by external and internal factors. In this review, the potential role of genetic, environmental, and endocrine factors; nutrients and trace elements in male reproductive health, spermatozoa function, and fertility potency and the underlying mechanisms are considered to provide a theoretical basis for clinical treatment of infertility.

Use of Exogenous Testosterone for the Treatment of Male Factor Infertility: A Survey of Nigerian Doctors

Background

Though exogenous testosterone is known for its contraceptive effects in men, it is sometimes prescribed by medical practitioners for the treatment of male factor infertility in the mistaken belief that exogenous testosterone improves sperm count. The aim of this study was to evaluate the scope of testosterone use in the treatment of male factor infertility by medical practitioners in Lagos, Nigeria.

Methods

A survey using a structured questionnaire was carried out amongst doctors attending a regular Continuing Medical Education (CME) programme in Lagos, Nigeria.

Results

There were 225 respondents. Most of the respondents (69.8%, n = 157) indicated that exogenous testosterone increases sperm count. Only 22 respondents (9.8%) indicated (correctly) that exogenous testosterone decreases sperm count. Seventy-seven respondents (34.2%) had prescribed some form of exogenous testosterone in the treatment of male factor infertility. The vast majority of respondents who had prescribed testosterone (81.8%, n = 63) thought exogenous testosterone increases sperm count. There was no statistically significant difference in the pattern of prescription across the respondents' specialty (p = 0.859) or practice type (p = 0.747).

Conclusion

The misuse of exogenous testosterone for the treatment of male infertility was common amongst the respondents, with most of them wrongly believing that exogenous testosterone increases sperm count.

Novel actions of progesterone: what we know today and what will be the scenario in the future?

Objectives

This article is aimed to review the novel actions of progesterone, which otherwise is considered as a female reproductive hormone. The article focuses on its important physiological actions in males too and gives an overview of its novel perspectives in disorders of central and peripheral nervous system.

Key findings

Progesterone may have a potential benefit in treatment of traumatic brain injury, various neurological disorders and male related diseases like benign prostatic hypertrophy (BPH), prostate cancer and osteoporosis. Norethisterone (NETA), a progesterone derivative, decreases bone mineral loss in male castrated mice suggesting its role in osteoporosis. In the future, progesterone may find use as a male contraceptive too, but still needs confirmatory trials for safety, tolerability and acceptability. Megestrol acetate, a progesterone derivative is preferred in prostatic cancer. Further, it may find utility in nicotine addiction, traumatic brain injury (recently entered Phase III trial) and Alzheimer's disease, diabetic neuropathy and crush injuries. Studies also suggest role of progesterone in stroke, for which further clinical trials are needed. The non genomic actions of progesterone may be in part responsible for these novel actions.

Summary

Although progesterone has shown promising role in various non-hormonal benefits, further clinical studies are needed to prove its usefulness in conditions like stroke, traumatic brain injury, neuropathy and crush injury. In male related illnesses like BPH and prostatic Ca, it may prove a boon in near future. New era of hormonal male contraception may be initiated by use of progesterone along with testosterone.

Anabolic steroids and semen parameters in bodybuilders

The influence of high-dose anabolic steroid administration on endocrine and semen parameters of 41 bodybuilders (age, 26.7 +/- 0.7 years [mean +/- SEM]; height, 182 +/- 1 cm; weight, 97.5 +/- 2.0 kg) was investigated. History of anabolic steroid administration was recorded retrospectively, and results of semen analysis were compared with data from 41 consecutively recruited normal volunteers not using any steroids or other drugs. Doses of anabolic steroids taken by bodybuilders exceeded those generally applied for clinical purposes by up to 40-fold. Although only 5 of the normal volunteers had sperm counts below the lower normal limit of 20 x 10(6) sperm/mL, 24 of the bodybuilders showed subnormal values. Depending on the duration of anabolic steroid use and the period since last drug intake before the investigation, percentages of motile and normally formed sperm were significantly reduced in bodybuilders compared with normal volunteers. In those bodybuilders who had stopped consumption of anabolic steroids greater than 4 months previously, sperm numbers were in the normal range. Results suggest that even after prolonged use of extremely high doses of anabolic steroids, sperm production may return to normal.

Suppression of sperm function by depot medroxyprogesterone acetate and testosterone enanthate in steroid male contraception

Ten normal men were given three monthly intramuscular injections of 200 mg of depot medroxyprogesterone acetate (MPA) and 250 mg of testosterone (T) enanthate. Six men became azoospermic, while four remained oligozoospermic, with a mean sperm density of 1.5 +/- 0.3 standard error of the mean million/ml. Zona-free hamster oocyte penetration was abolished in all oligozoospermic samples at the end of treatment. Twenty of the 21 oligozoospermic samples yielding at least 0.6 to 5.0 million motile spermatozoa showed a complete absence of oocyte penetration. Semen parameters returned to normal, although some took up to 12 months. These findings demonstrated an antifertility action of MPA and T enanthate on the functional capacity of residual spermatozoa and support the view that extreme oligozoospermia may be a tenable target for reversible steroid male contraception.