It says if inserted within five days of unprotected sex, an IUD which is also a regular contraception method can be up to 99 percent effective in preventing pregnancy following sexual assault, incorrect use of contraceptives or unprotected sex.
“This is the most effective form of emergency contraception available,” says the WHO.
It says once inserted, a woman can continue to use the IUD as an ongoing method of contraception and may choose to change to another contraceptive method in future.
“This may be an ideal emergency contraceptive for a woman who is hoping for an ongoing, highly effective contraceptive method,” WHO says in its website.
It says as an emergency contraception, IUD’s primarily prevent fertilisation by causing a chemical change that damages sperm and egg before they can meet.
“A copper bearing IUD is a very safe form of emergency contraception. The risks of infection, expulsion or perforation are low.”
However, the global health body has cautioned that IUD’s are not to be used if a woman is already pregnant. It adds that there are other contraindications to using a copper bearing IUD as ongoing contraception which should also be considered before its use as emergency contraception.
WHO has also approved a new pill known as levonorgestrel for emergency contraception to be taken as one dose within five days of unprotected sex.
It says the recommendation of levonorgestrel pill was based on reports from nine studies including 10,500 women that proved that the pill was between 52 and 94 percent effective in preventing pregnancy depending on how soon it was taken.
“Alternatively, a woman can take the levonorgestrel in two doses, 12 hours apart,” it says.
Levonorgestrel emergency contraceptive pills prevent pregnancy by delaying or preventing ovulation. They are said to be safe and do not cause abortion or harm future fertility.
“Side effects are uncommon and generally mild. If a woman inadvertently takes the pills after she becomes pregnant, the available evidence suggests that the pills will not harm either the mother or her foetus.”
Emergency contraception is effective only in the first few days following intercourse before the ovum is released from the ovary and before the sperm fertilises the ovum. Emergency contraceptive pills cannot interrupt an established pregnancy or harm a developing embryo.