Contraceptive device

Claim 1

A contraceptive device comprising: an open cylindrical body having upper and lower ends, said body adapted for insertion in the cervix with its sides contacting the sides of the cervix preventing fluid passage therebetween; retention means to retain said cylindrical body in position in the cervix said retention means having a plurality of wires extending from the upper end of said cylindrical body, said wires bending outward and downward to form hooks which are adapted to be engaged in the cervico-uterine junction; valve means to allow passage of menstrual fluid through said cylindrical body, said valve means further adapted to block passage of semen to the uterus, said valve means having an elliptical flap hingeably attached within said cylindrical body, said flap extending downward adapted in a first mode to be urged against the inside walls of said cylindrical body; and a spring member adapted to urge said flap against the walls of said cylindrical body, said spring member having only sufficient force to hold said flap in a closed first mode, said spring member being further adapted to compress and allow said flap to open upon slight pressure from menstrual fluid from above, said flap adapted to remain in a closed mode when pressured from below to block semen flow coming from the lower end of said cylindrical body.