Intrauterine device

An intrauterine device for preventing egg fertilization comprising:

• a) a membrane;
• b) a frame having a first arm and a second arm, the first and second arms movable from a first position to a second more expanded position, wherein the first and second arms each have a curve extending outwardly, the frame supporting the membrane to move the membrane between a first position to a second more expanded position, wherein the first and second arms are non-planar and each arm has a proximal portion, an intermediate portion and a distal portion, the first arm has a first bend at the intermediate portion so the intermediate portion of the first arm lies in a different plane than the proximal portion of the first arm and the second arm has a second bend at the intermediate portion so the intermediate portion of the second arm lies in a different plane than the proximal portion of the second arm, the membrane at an intermediate region curving inwardly toward a distal region due to the first and second bends;
• and
• c) an elongated tail portion positioned proximal of the membrane.