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Updated: Jun 26, 2025

Establishment of Rat Models Mimicking Gender-affirming Hormone Therapies
Published on: January 10, 2025
Development of new hormonal male contraception for the couple
Jeffrey M Kroopnick1, Min S Lee1, Diana L Blithe1
1Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA.
Background:
Current options for male contraception are limited to condoms, the withdrawal method, or a vasectomy. Studies indicate that men have expressed growing interest in bearing responsibility for family planning.
Objectives:
To review prior studies investigating the role of an androgen-only or androgen with progestin regimen for hormonal male contraception and to provide an update of a promising new hormonal agent, a transdermal gel.
Discussion:
Thus far, there have been six studies conducted in couples evaluating the contraceptive efficacy of an androgen-only or androgen co-administered with a progestin regimen for hormonal male contraception. The only ongoing study is by the National Institute of Child Health and Human Development, in collaboration with the Population Council. They have developed a novel transdermal gel containing testosterone and segesterone acetate (Nestorone), a progestin. An ongoing phase II study enrolling more than 460 couples has shown great potential with respect to the product's efficacy, safety, reversibility, and acceptability. As this agent advances in development, a rapid at-home test for sperm concentration will provide couples with immediate feedback regarding their potential for pregnancy.
Conclusion:
There is promise for the first-of-its-kind hormonal male contraceptive, a transdermal gel, to achieve market approval for distribution in the United States and elsewhere. Its safety, efficacy, reversibility, and user-control are all appealing qualities that make it readily adoptable for clinical practice.
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