Paragard is a hormone-free method of birth control that relies on copper to prevent fertilization. The copper thickens the consistency of the cervical mucus, greatly hindering sperm motility. Since there are no hormones, the woman continues to ovulate. Other intrauterine devices on the market are hormonal birth control methods. Examples of this form of birth control include Mirena, Kyleena, Skyla, and Liletta, which rely on progestin (levonorgestrel) to prevent fertilization. They are inserted and removed in the same manner as the Paragard IUD.