Rethinking the application of nanoparticles in women’s reproductive health and assisted reproduction

Nanoparticles and nanotechnology may present opportunities to revolutionize the prevention, treatment and diagnosis of a range of reproductive health conditions in women. These technologies are also used to improve outcomes of assisted reproductive technology. We highlight a range of these potential clinical uses of nanoparticles for polycystic ovary syndrome, endometriosis, uterine fibroids and sexually transmitted infections, considering in vitro and in vivo studies along with clinical trials. In addition, we discuss applications of nanoparticles in assisted reproductive technology, including sperm loading, gamete and embryo preservation and preventing preterm birth. Finally, we present some of the concerns associated with the medical use of nanoparticles, identifying routes for further exploration before nanoparticles can be applied to women’s reproductive health in the clinic. What opportunities do nanoparticles present to revolutionize the prevention, treatment and diagnosis of reproductive health conditions in women and improve outcomes of assisted reproductive technology? Metal nanoparticles can exhibit direct effects on polycystic ovary syndrome, reducing insulin resistance and inflammation. Lipid-based nanoparticles significantly increase the bioavailability of existing polycystic ovary syndrome treatment drugs. Nanoparticles provide a possible nonsurgical route for endometriosis diagnosis, while also potentially linking lesion identification and treatment through coupling imaging agents to nanoparticles with high heating efficiency to induce local hyperthermia. Endometriosis-related inflammation, oxidative stress and angiogenesis have all been reduced in animal endometriosis models by the addition of nanoparticles. Nanoparticles aid both in traditional treatment methods (as an embolic material) and in the delivery of interfering peptides, nucleic acids and drugs that can reduce fibroid size. Nanoparticles may allow the rapid diagnosis of sexually transmitted infections such as gonorrhea and chlamydia through gold nanoparticle biosensors. Nanoparticles can improve traditional contraceptive methods: silver nanoparticles, exhibiting antimicrobial effects, can be used to coat condoms or to reduce biofilm formation on intrauterine devices. Nanoparticles may be an effective way to formulate vaccinations against sexually transmitted infections due to their in vivo trafficking, ability to present multimeric antigens and enhanced immunogenic responses. Magnetic nanoparticles and mesoporous silica nanoparticles have been successfully used to interact with sperm and also to carry biological factors such as nucleic acids and proteins. This may allow missing or defective factors to be replaced during assisted reproductive technology to aid fertility. Oxidative stress induced by cryopreservation of gametes can be reduced by the use of nanoparticles either as part of the freezing medium or via membrane-lipid replacement. Nanoparticles increase the heating efficiency of cryopreserved gametes and embryos in a safe and effective manner.