Metronidazole, the U.S. Food and Drug Administration-approved drug against trichomoniasis, is nonspermicidal and thus cannot offer pregnancy protection when used vaginally. Furthermore, increasing resistance of Trichomonas vaginalis to 5-nitro-imidazoles is a cause for serious concern. On the other hand, the vaginal spermicide nonoxynol-9 (N-9) does not protect against sexually transmitted diseases and HIV in clinical situations but may in fact increase their incidence due to its nonspecific, surfactant action. We therefore designed dually active, nonsurfactant molecules that were capable of killing Trichomonas vaginalis (both metronidazole-susceptible and -resistant strains) and irreversibly inactivating 100% human sperm at doses that were noncytotoxic to human cervical epithelial (HeLa) cells and vaginal microflora (lactobacilli) in vitro . Anaerobic energy metabolism, cell motility, and defense against reactive oxygen species, which are key to survival of both sperm and Trichomonas in the host after intravaginal inoculation, depend crucially on availability of free thiols. Consequently, molecules were designed with carbodithioic acid moiety as the major pharmacophore, and chemical variations were incorporated to provide high excess of reactive thiols for interacting with accessible thiols on sperm and Trichomonas . We report here the in vitro activities, structure-activity relationships, and safety profiles of these spermicidal antitrichomonas agents, the most promising of which was more effective than N-9 (the OTC spermicide) in inactivating human sperm and more efficacious than metronidazole in killing Trichomonas vaginalis (including metronidazole-resistant strain). It also significantly reduced the available free thiols on human sperm and inhibited the cytoadherence of Trichomonas on HeLa cells. Experimentally in vitro , the new compounds appeared to be safer than N-9 for vaginal use.

We do not seem to be the only owner of our body; it houses a large population of microorganisms. Through countless years of coevolution, microbes and hosts have developed complex relationships. In the past few years, the impact of microbial communities on their host has received significant attention. Advanced molecular sequencing techniques have revealed a remarkable diversity of the organ-specific microbiota populations, including in the reproductive tract. Currently, the goal of researchers has shifted to generate and perceive the molecular data of those hidden travelers of our body and harness them for the betterment of human health. Recently, microbial communities of the lower and upper reproductive tract and their correlation with the implication in reproductive health and disease have been extensively studied. Many intrinsic and extrinsic factors influences the female reproductive tract microbiota (FRTM) that directly affects the reproductive health. It is now believed that FRTM dominated by Lactobacilli may play an essential role in obstetric health beyond the woman’s intimate comfort and well-being. Women with altered microbiota may face numerous health-related issues. Altered microbiota can be manipulated and restored to their original shape to re-establish normal reproductive health. The aim of the present review is to summarize the FRTM functional aspects that influence reproductive health.