The NICHD relies on several organizational units to study different aspects of male reproductive health. The information below describes a few of these activities.
Institute Activities and Advances
Much of the Institute's research on contraceptive agents and their evaluation is done through the Contraceptive Discovery and Development Branch (CDDB). The CDDB is the largest source of support for research on contraception within the federal government. It has responsibility for contraception research and development and for contraceptive and reproductive evaluation.
Using a combination of grants and contracts, the Branch supports and/or conducts the following activities:
- Phase I, II, III, or IV clinical trials to evaluate the safety and efficacy of new contraceptive methods for women and men
- Research to develop methods for male contraception, including hormonal and nonhormonal control of sperm production and/or sperm function
- Experimental studies in animals to determine the safety and efficacy of novel potential contraceptive agents
The Institute's Population Dynamics Branch funds studies of sexual behaviors and their relationship to disease prevention in a variety of populations. This includes basic and intervention research on the demographic, social, and behavioral aspects of the sexual transmission of HIV and other sexually transmitted diseases.
At the Fertility and Infertility (FI) Branch, the mission is to alleviate infertility, discover new leads on contraceptives, and expand basic scientific knowledge about human reproduction.
Researchers in the Institute's Division of Intramural Research investigate the molecular basis of peptide hormone control of gonadal function, with particular emphasis on the structure and regulation of the luteinizing hormone and prolactin (PRL) receptor (PRLR) genes, concentrating studies on the function and regulation of gonadotropin-regulated testicular RNA helicase (GRTH/DDX25), an essential post-transcriptional regulator of spermatogenesis that was discovered, cloned, and characterized in their laboratory. The various functions of GRTH/DDX25 provide fertile ground for the development of a male contraceptive.
Research efforts from these organizational units have led to the following scientific advances related to men's reproductive health.
Potential Nonhormonal Male Contraceptive
Despite decades of research into hormonal and immunological methods of male contraception, no regimen based on either of these approaches is near clinical approval. Compounds called bisdichloroacetyldiamines have been shown to safely and effectively suppress spermatogenesis in men. However, these compounds also cause an adverse reaction when co-administered with alcohol, and this has prevented their introduction for contraceptive purposes. Researchers supported by the NICHD and the National Institute of General Medical Sciences have now demonstrated that the contraceptive effect of these compounds is mediated by inhibition of testicular retinoic acid biosynthesis via a specific enzyme. This finding may allow for the development of novel, specific inhibitors of spermatogenesis that do not cause the adverse reaction and can be developed into a safe, effective, and reversible form of male contraception. For more information on this finding, visit http://www.ncbi.nlm.nih.gov/pubmed/20705791.
Home Fertility Test for Men
Every year, more than 7 million couples report having infertility problems. About one-third of infertility cases are the result of male issues, one-third are due to female issues, and the other third are due to combined issues of the couple or are unknown. Although home fertility tests are available to women, male fertility tests have typically been available only through health care providers.
SpermCheck Fertility® is a newly developed test that allows men to check their sperm count in the privacy of their homes. The test takes about ten minutes and involves adding semen samples to a plastic cartridge, which resembles and gives a similar reading as a pregnancy test. After adding the semen sample, the appearance of lines on an indicator strip tells the user if the sperm count is normal, low, or very low. Since sperm count is one of the first things tested in a fertility clinic, the new test now allows this to be quickly and inexpensively checked with a home test. This home test for men is an important addition to home fertility tests, which provide valuable, private information to couples experiencing fertility problems. For more information on this research, visit http://www.ncbi.nlm.nih.gov/pubmed/20139122.
Other Activities and Advances
The CDDB supports the following research efforts related to men’s reproductive health:
- The Contraceptive Clinical Trials Network (CCTN)conducts clinical trials of new contraceptive drugs and devices. The CCTN includes two sites specifically for evaluating male contraceptives. Network research includes studies of progestin- and testosterone-based topical gels designed to reduce gonadotropin levels and reversibly inhibit sperm production in order to provide effective, user-controlled hormonal contraception for men.
- The Male Contraceptive Development Program (MCDP) conducts a wide range of research with the ultimate goal of developing useful contraceptive products for men. Research focuses for the MCDP include studies on:
- Mechanisms regulating how spermiogenesis might be targeted by novel male contraceptives
- Signaling pathways for the protein receptor c-Ros in male fertility
- Sperm glycolytic enzymes
- Nonhormonal targets for male contraception, including the tight junctions between Sertoli cells and germ cells, which are required for appropriate cell-cell interactions during sperm development (spermatogenesis)
- Injectable formulation of acyline, a potent gonadotropin-releasing hormone antagonist, to assess drug safety and ability to suppress spermatogenesis
- Novel male contraceptives, including H2-gamendazole, an orally active anti-spermatogenic compound
- Pharmaceutical targeting of a sperm-specific calcium cation channel (CatSper) and consequences of targeting on male fertility
- The Contraceptive Development Research Center Program aims to identify new contraceptive products. The centers are interactively organized to allow research on discovering and/or developing promising new leads for regulation of fertility, as well as additional relevant projects. Individual projects focus on basic, preclinical, or clinical research, or on a combination of these areas related to topics in both women’s and men’s reproductive health.
- The Male Reproductive Health Research Career Development Program was established in 2006 to advance the career development of clinicians who specialize in male reproductive health. The program aims to increase the clinical research capacity of practitioners in male reproductive biology and promote the translation of basic research to clinical practice