Re: Birth Control Pills and Condoms…
It doesn’t release chemicals.
http://www.mcgill.ca/studenthealth/information/womenshealth/contraception/iud/
An IUD is a small, plastic or plastic and copper device attached to a pair of thin plastic threads which is inserted into the uterus. Its exact mechanism of action is not known, but it is believed to involve a change in the lining of the uterus which prevents implantation of a fertilized egg which is then expelled during the menstrual period.