It is used for contraception which helps to avoid pregnancy and for irregular menstual period treatment in different ways. It helps to avoid release and fertilization of the egg. It prevents an egg from being released from the ovaries. It also makes the mucus in your cervix thicker, which makes it difficult for sperm to enter the womb. Additionally, it prevents thickening of the lining of your womb, thereby making it unfavourable for an egg to grow in it.