Which of the following is not a natural method of contraception?

Intra uterine devices

The correct answer is Option (4) → Intra uterine devices

An effective and popular method of contraception is the use of Intra Uterine Devices (IUDs). These devices are inserted by doctors or expert nurses in the uterus through the vagina. These Intra Uterine Devices are presently available as the non-medicated IUDs (e.g., Lippes loop), copper-releasing IUDs (CuT, Cu7, Multiload 375) and the hormone-releasing IUDs (Progestasert, LNG-20).

Natural methods work on the principle of avoiding chances of ovum and sperms meeting.Example : Periodic abstinence, Withdrawal or coitus interruptus, Lactational amenorrhea .

Periodic abstinence is one such method in which the couples avoid or abstain from coitus from day 10 to 17 of the menstrual cycle when ovulation could be expected. As chances of fertilisation are very high during this period, it is called the fertile period. Therefore, by abstaining from coitus during this period, conception could be prevented.

Withdrawal or coitus interruptus is another method in which the male partner withdraws his penis from the vagina just before ejaculation so as to avoid insemination.

Lactational amenorrhea (absence of menstruation) method is based on the fact that ovulation and therefore the cycle do not occur during the period of intense lactation following parturition. Therefore, as long as the mother breast-feeds the child fully, chances of conception are almost nil. However, this method has been reported to be effective only upto a maximum period of six months following parturition. As no medicines or devices are used in these methods, side effects are almost nil. Chances of failure, though, of this method are also high.