MeriTe Cu 250 is an intrauterine device with a multi-load design. It is made with a combination of high-density polyethylene, ethylene vinyl acetate copolymer and barium sulphate. A 99% pure copper wire is wound around the stem, giving a total copper surface area of 250mm². The monofilament nylon thread is attached to the stem.
MeriTe Cu 250 primarily works by disrupting sperm mobility and damaging sperm. It acts as a spermicide within the uterus. It increases levels of copper ions, prostaglandins, and white blood cells within the uterine and tubal fluids. Increased ions inhibit sperm mobility and viability, preventing sperm from traveling through the cervical mucus.