The search for improvements to contraceptive methods continues. The majority of research projects are focused on methods employed by women. Firstly, they are less complicated in a medical sense than those used by men (ovulation once a month is easier to suppress than the production of several hundred million sperm each day.)
Secondly, women want to maintain control over their own bodies, rather having to depend on the cooperation of and correct application by their partners.
Developing new methods of birth control has become more expensive and difficult than it was 50 years ago because an innovation must be better than all the methods that proceed it.