Someone asked.... so

IUD's work in a couple of ways... firstly they irritate the cervix into making thicker mucus which is more difficult for sperm to get through...

but if sperm does get through and contraception occurs...

they are also though to increase motility in the fallopian tubes so that any "products of conception" pass through the uterine cavity before it is ready to implant

some of them also contain copper which irritates the lining of the womb (endometrium)making it less likely for implantation to occur... and it may increase prsotaglandin production, making expulsion of any conceptus more likely...

(Info taken from "Myles Textbook for Midwives")

combined with spermicide (kill them before they get through)or whatever... it's as effective as "the pill"......

but in this day and age... unless you are in a monogamous relationship with a partner you are very sure of - the barrier methods will keep you safer ........

contraceptive choices and information

slainte

alison