Hormonal Male Contraception

Abstract

Currently, available female methods of contraception include the combined estrogen-progesterone oral contraceptive pill, progestin-only pills, 3-monthly depomedroxyprogesterone acetate (DMPA) injections, levonorgestrel (LNG)-containing implants (Norplant), copper intrauterine devices, vaginal rings, female condoms, tubal ligation, menses inducers (mifepristone [RU486] and misoprostol [prostaglandin E1]), and emergency contraception using estrogens. Other less effective methods include natural family planning, lactation amenorrhea, and vaginal spermicides. Recent pharmaceutical developments and introductions of new or improved methods include ultra-lowdose estrogen-progestin combination pills, emergency contraception with oral tablets containing LNG or mifepristone alone, combination of estradiol cypionate and DMPA monthly injections, low-dose LNG-releasing intrauterine devices, transdermal skin patches delivering low-dose estrogens plus progestins, single implant systems delivering etonorgestrel, and nesterone (a progestin) vaginal rings. These new methods will provide an even wider choice of contraceptive methods for women. Other female methods under preclinical or early clinical development include the following: immunocontraception using antisperm antibodies, anti-zona-pellucida antibodies, or anti-hCG vaccine; new injectable progesterone esters; and new vaginal spermicides with antiviral activities that will provide dual protection (against pregnancy and sexually transmitted infections). In contrast, the currently male-controlled methods are limited to coitus interruptus, male condoms, and vasectomy.