An inserter for placing a T-shaped intrauterine device inside a patient's uterus and a T-shaped intrauterine device are disclosed. The inserter includes a sleeve part and a plunger part, the sleeve part includes a tube and a first engaging member and the plunger part includes a rod, a handle attached to the rod and a second engaging member. The first and the second engaging members are configured for reversibly engaging the sleeve part and the plunger part to temporarily lock the relative position between the tube and the rod. The T-shaped intrauterine device includes a pair of wings having a relaxed extended configuration and a contracted folded configuration and an elongated contraceptive body suspended from a junction between the wings.