Androgens in Health and Disease.pdf - E Library

Chapter 21/Androgens and Male Contraception 411
Fig. 3. Progestins used in male contraceptive research: (A) Medroxyprogesterone acetate;
(B) levonorgestrel; (C) cyproterone acetate; (D) desogestrel; (E) norethisterone enanthate.
trial of LNG (500 µg orally daily) with TE (100 mg im/wk) showed the LNG–TE
combination was superior to TE alone in terms of azoospermia (67% vs 33%) by 6 mo
(44). In addition, the total achieving either severe oligozoospermia or azoospermia was
94% in the LNG–TE group compared to 61% of the TE-alone group. Drawbacks to the
LNG–TE regimen included greater weight gain and decreases in HDL cholesterol when
compared to the TE-alone group. Recently, the same research group demonstrated that
lower doses of LNG were as effective at achieving azoospermia, but weight gain and
reductions of HDL cholesterol were minimized with the decreased dose of LNG (45).
LNG has recently been tested in combination with 1000 mg of TU injected every 6 wk;
however, there was no additive benefit of LNG in terms of suppression of spermatogenesis
when compared to TU alone in this study (16).
Another new progestin, desogestrel (DSG; see Fig. 3C), has been recently tested in
male contraceptive regimens (46,47). DSG differs from LNG only by a methylene
group in the 11 position, however, it is thought to possess less inherent androgenicity
than LNG. In both studies, 150 or 300 µg of DSG daily was combined with 50- and