Male Hormonal Contraception: Looking Back and Moving Forward

The document reviews the progress and challenges in the development of male hormonal contraception, emphasizing the need for new reversible options given the high rate of unplanned pregnancies. Clinical trials involving over 2000 men have shown that hormonal regimens can suppress spermatogenesis and that normal sperm production returns upon cessation. Testosterone alone has limitations, leading to studies combining testosterone with progestins, which have shown improved sperm suppression and tolerability. A phase IIb study in China with testosterone undecanoate achieved a 97% efficacy rate, while a phase III study reported a 95% efficacy rate. Other potential contraceptives like Nestorone/testosterone gels and synthetic androgens like DMAU and MENT are being explored. The document notes the need for further research on the long-term effects on bone mineral density and cardiovascular health, and highlights the challenges of funding, the need for larger trials, and variability in efficacy. The majority of funding comes from the Eunice Kennedy Shriver National Institute for Child Health and Human Development, and the document concludes with a call for continued development of male contraceptives to enable shared responsibility in family planning.