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Methods Of Birth Control In Humans

Features of an ideal contraceptive

  • User-friendly
  • Easily available
  • Effective and reversible
  • No or least side-effects
  • It should not interfere with sexual desire or sexual drive or in the sexual act of the consumer.

Contraceptives methods are available in a wide range and can be broadly categorised as:

  • Natural or traditional – These work on the principle of avoiding chances of the meeting of sperm and ovum.
    Periodic abstinence is a method in which the partners avoid or refrain from coitus between 10 to 17 day of the menstrual cycle when the ovulation is due. During this period the chances of fertilization are very high, thus called the fertile period.
    Abstaining intercourse during this period can prevent conception.
    Coitus interruptus or withdrawal
    Coitus interruptus or withdrawal is another method in which the male partner removes his penis from the vagina just before discharge to avoid insemination.
    Lactational amenorrhea
    It is the absence of menstruation. During intense lactation, ovulation does not occur, and hence menstruation also remains absent. Therefore, the period during which the mother feeds the child, chances of conception becomes negligible. However, this method is effective only up to a maximum of six months.
    The natural methods do not have side effects but these are not a hundred percent effective, and chances of conception are quite high.
  • Barrier – In this method, the sperm and ovum are prevented from meeting with the help of barriers. Such methods are available for both male and female.
    • Condoms – These are made of rubber or thin latex sheath that cover the penis or vagina and cervix. These are used just before coitus so that semen can be prevented from entering into the female reproductive tract. This can prevent conception. The use of condoms also ensures the prevention of sexually transmitted diseases (STIs) and AIDS. Condoms are disposable and can be self inserted and thus gives privacy to the user.
    • Diaphragms, vaults and cervical caps are also some other types of barriers that are made of rubber that can be inserted into the female reproductive tract to coat the cervix during intercourse. These prevent the conception by restricting the entry of sperms through the cervix. These can be used again.
    • Spermicidal creams, foams and jellies are also used with these barriers to enhance the contraceptive efficiency.
    • Advantages of this method – These products, especially condoms are easily available and also protect from sexually transmitted diseases.
    • Disadvantage of this method – These are not completely reliable especially if not used properly or condoms break due to some reason.
  • IUDs (Intrauterine Devices) – Another effective method of contraception. In this, some devices are inserted in the vagina through the uterus. These are done by doctors only. These are presently available as non-medicated IUDs, copper-releasing IUDs, and the hormone-releasing IUDs. IUDs work by increasing the phagocytosis of sperms within the uterus and the release of Cu ions which suppress the motility of the sperm and fertilizing capacity of sperms.

  • The hormone-releasing IUDs changes the overall environment of the uterus and makes it unsuitable for implantation and also makes the cervix aggressive to the sperms. It is a good alternative for females who want to delay pregnancy or want space in the next conception after one child.
  • Oral contraceptives – Oral contraceptives come in the form of pills and are taken in small doses. These comprise of either progestogens or the combination of progestogens and estrogen. It has to be taken daily for a period of 21 days starting preferably within the first five days of the menstrual cycle. It has to be repeated in the same pattern after a gap of seven days during which the menstruation occurs. It should be continued until the female wants to prevent conception. These pills inhibit ovulation and implantation as well as change the quality of cervical mucus to prevent or retard the entry of sperms. It is a very efficient method of contraception.
    • Advantages – easy to take pill
    • Disadvantages – Some side effects like mood swings, weight gain, increased risk of blood clots are observed. Also, it does not protect against STIs.
  • Injectables – Progestogens or combination of progestogens and estrogen can be used by females as injections or implants under the skin. Their works like a pill and they are effective for a long time. Usage of these in combination with IUDs within 72 hours of intercourse makes this method quite effective. It is also useful in avoiding pregnancy in the case or rape or casual unprotected intercourse.

  • Surgical methods – The methods like sterilization involve surgery of the reproductive organ in which either male or female partner adopt a terminal method to prevent pregnancy. Surgery is done to block the gamete transfer and thereby prevent conception. In males, this procedure is called vasectomy, and in females, it is called tubectomy.
    • Vasectomy – A small portion of vas deferens is tied up or removed through a small cut on the scrotum.
    • Tubectomy – A small portion of the fallopian tube is removed or tied up through a small cut in the abdomen or vagina.
      These methods are quite efficient in the prevention of pregnancy but once done; these can’t always be reversed.

It needs to be noted that the selection of an appropriate contraceptive method and its use should always be taken in consultation with qualified medical specialists.

Contraceptives are not regular needs for the regulation of reproductive health. In fact, they are done against a natural reproductive activity, i.e., conception or pregnancy. It is used either to check pregnancy or to pause or space pregnancy due to individual reasons. No doubt, the extensive use of these methods have an essential role in preventing the uncontrolled growth of population. However, their possible negative effects like nausea, bleeding, abdominal pain, irregular menstrual bleeding or even breast cancer (not significant effect) should not be overlooked.