It looks like it is not 100% effective. Now maybe if your testosterone is suspended in cotton seed oil that will help a bit more since cotton seed is also is being looked at for a male contraceptive.
1: Curr Opin Endocrinol Diabetes Obes. 2008 Jun;15(3):255-60.Click here to read
Progress and prospects in male hormonal contraception.
Amory JK.
Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington, Seattle, Washington 98195, USA.
[email protected]
PURPOSE OF REVIEW: Testosterone functions as a contraceptive by suppressing the secretion of luteinizing hormone and follicle-stimulating hormone from the pituitary. Low concentrations of these hormones deprive the testes of the signals required for spermatogenesis and results in markedly decreased sperm concentrations and effective contraception in a majority of men. Male hormonal contraception is well tolerated and acceptable to most men. Unfortunately, testosterone-alone regimens fail to completely suppress spermatogenesis in all men, meaning that in some the potential for fertility remains. RECENT FINDINGS: Because of this, novel combinations of testosterone and progestins, which synergistically suppress gonadotropins, have been studied. Two recently published testosterone/progestin trials are particularly noteworthy. In the first, a long-acting injectable testosterone ester, testosterone decanoate, was combined with etonogestrel implants and resulted in 80-90% of subjects achieving a fewer than 1 million sperm per milliliter. In the second, a daily testosterone gel was combined with 3-monthly injections of depot medroxyprogesterone acetate producing similar results. SUMMARY: Testosterone-based hormone combinations are able to reversibly suppress human spermatogenesis; however, a uniformly effective regimen has remained elusive. Nevertheless, improvements, such as the use of injectable testosterone undecanoate, may lead to a safe, reversible and effective male contraceptive.
1: J Clin Endocrinol Metab. 2008 May;93(5):1774-83. Epub 2008 Feb 26.Click here to read Links
Determinants of the rate and extent of spermatogenic suppression during hormonal male contraception: an integrated analysis.
Liu PY, Swerdloff RS, Anawalt BD, Anderson RA, Bremner WJ, Elliesen J, Gu YQ, Kersemaekers WM, McLachlan RI, Meriggiola MC, Nieschlag E, Sitruk-Ware R, Vogelsong K, Wang XH, Wu FC, Zitzmann M, Handelsman DJ, Wang C.
Department of Andrology, ANZAC Research Institute, University of Sydney and Concord Hospital, Concord, New South Wales 2139, Australia.
[email protected]
CONTEXT: Male hormonal contraceptive methods require effective suppression of sperm output. OBJECTIVE: The objective of the study was to define the covariables that influence the rate and extent of suppression of spermatogenesis to a level shown in previous World Health Organization-sponsored studies to be sufficient for contraceptive purposes (< or =1 million/ml). DESIGN: This was an integrated analysis of all published male hormonal contraceptive studies of at least 3 months' treatment duration. SETTING: Deidentified individual subject data were provided by investigators of 30 studies published between 1990 and 2006. PARTICIPANTS: A total of 1756 healthy men (by physical, blood, and semen exam) aged 18-51 yr of predominantly Caucasian (two thirds) or Asian (one third) descent were studied. This represents about 85% of all the published data. INTERVENTION(S): Men were treated with different preparations of testosterone, with or without various progestins. MAIN OUTCOME MEASURE: Semen analysis was the main measure. RESULTS: Progestin coadministration increased both the rate and extent of suppression. Caucasian men suppressed sperm output faster initially but ultimately to a less complete extent than did non-Caucasians. Younger age and lower initial blood testosterone or sperm concentration were also associated with faster suppression, but the independent effect sizes for age and baseline testicular function were relatively small. CONCLUSION: Male hormonal contraceptives can be practically applied to a wide range of men but require coadministration of an androgen with a second agent (i.e. progestin) for earlier and more complete suppression of sperm output. Whereas considerable progress has been made toward defining clinically effective combinations, further optimization of androgen-progestin treatment regimens is still required.
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