Bleeding from the uterus is the most frequent side effect from using an intra uterine device (IUD). There are 3 types of bleeding while wearing an IUD: heavier menstruations (hypermenorrhea), prolonged menstruations (menorrhage) and inter-menstrual bleeding (spotting). Normally after inserting IUD, there is a weak bleeding present that usually lasts for up to 20 days... but it can also lasts up to 3-4 months. After that period, the bleeding should disappear. Such bleeding is usually accompanied with pain due to uterine cramps. If the bleeding is too heavy and causes anemia, the IUD should be removed. You should consult your gynecologist about this issue and seek resolution.