Regarding contraception, despite the availability of a range of contraceptive methods, over 50% of pregnancies are unintended worldwide and in the United States. Thus, there is a critical need for contraception that better fits the diverse needs of women and men and takes into consideration different ethnic, cultural and religious values. Projects in our group are focused to find innovative methods for male and female contraception.
Except for the use of condoms or vasectomy, the availability of contraceptive methods for men is very limited. A recent study shows that a high percentage of men are prepared to use a male contraceptive pill. Regarding this approach, only steroidal hormonal treatments have reached the clinical development stage. Supraphysiological doses of testosterone alone or in combination with a progestin are known to induce severe oligo- or azoospermia in male by a negative feedback regulation of the pituitary gland and subsequent reduction of LH and FSH. This approach has drawbacks such as the slow onset of infertility, the slow recovery of fertility and also the high doses of hormones used. Given the general safety and efficacy requirements imposed on any contraceptive method, as well as the anticipated undesired side-effects and problems with regard to the complete reversibility of fertility, there is a clear unmet need for alternative approaches to male fertility control.
Regarding female contraception, although currently available contraceptives are very effective, they rely on user's compliance for their maximal effectiveness; the consequence of this is that about half of unintended pregnancies are due to incorrect or inconsistent use. Increased use of long-acting reversible contraceptives (LARCs), among them intrauterine devices (IUDs), is considered at present the best solution to overcome this problem. Once in place, IUDs are the most effective form of reversible contraception available. Despite their high effectiveness, these forms of reversible contraception have not reached full potential in the United States and other countries. The most commonly reported IUD side effects are increased menstrual bleeding, IUD expulsion, cramping and, although not common, uterine perforation, a more serious adverse effect. Developing new contraceptives is a major challenge and industry is reluctant to take the risk of a long-term investment because of the high development/regulatory costs and the cultural challenges that will need to be overcome. However, improvement of existing IUD devices with respect to side effects is predicted to increase their acceptance and would constitute a significant advance in preventing unintended pregnancies. Our group at the University of Massachusetts has developed a new IUD that allows self-assembly inside the uterus. The focus of our research is to extend the application of this magnetic IUD for the use in women as a LARC. This device, compared with others in the market, would have the advantages of easier insertion and retrieval. It also has a better ergonomic fit inside the uterus that might be expected to reduce the side effects due to ergonomic design and initial insertion. This magnetic-based IUD has been patented and has been tested in horses where it has been shown to effectively prevent the mare estrous cycles.