Natural and barrier methods

Natural methods work by avoiding any meeting of ovum and sperms.

Periodic abstinence: the couple avoids coitus from day 10 to day 17 of the menstrual cycle, when ovulation is expected. Because fertilisation is most likely then, this stretch is called the fertile period.

Withdrawal (coitus interruptus): the male withdraws the penis from the vagina just before ejaculation, so no semen is deposited.

Lactational amenorrhea (absence of menstruation): during intense breast-feeding after parturition, ovulation and the cycle do not occur, so while the mother feeds the baby fully the chance of conception is almost nil. It works only up to at most six months after parturition.

Natural methods use no drugs or devices, so side effects are almost nil, but their failure rate is high.

Barrier methods physically stop ovum and sperms from meeting; they exist for both males and females.

Condoms are thin rubber or latex sheaths that cover the penis (male) or the vagina and cervix (female) just before coitus, so semen does not enter the female tract. Nirodh is a popular brand of male condom.

Condoms also protect the user from STIs and AIDS, which has raised their use. Both kinds are disposable and can be self-inserted, giving privacy.

Diaphragms, cervical caps and vaults are rubber barriers placed in the female tract to cover the cervix during coitus, blocking sperm entry. Unlike condoms, they are reusable.

Spermicidal creams, jellies and foams are usually used with these barriers to make them more effective.