Population Explosion Birth Control

4.2 Population Explosion and Birth Control

The world population, which was around 2 billion in 1900, rose sharply to about 6 billion by 2000 and crossed 7.2 billion in 2011. India's own population, just 350 million at independence in 1947, reached close to 1 billion by the 2000s and is currently near 1.4 billion — making us one of the most populous countries on Earth. Such a steep rise is called population explosion.

4.2.1 Steps to Check Population Growth

The Government of India took several effective steps to control runaway growth: motivational campaigns and slogans (Hum Do Hamare Do), raising the legal age of marriage (18 years for females, 21 years for males), and free, easily available contraceptives.

4.2.2 Classification of Contraceptive Methods

Contraceptive methods can be broadly grouped into the following categories: Natural / Traditional, Barrier, IUDs, Oral / Injectable, Implants, and Surgical (terminal) methods.

(a) Natural Methods

Work on the principle of avoiding chances of ovum and sperm meeting. They have no side-effects but the failure rate is relatively high.

• Periodic abstinence: Couples avoid coitus from day 10 to day 17 of the menstrual cycle (the fertile period when ovulation is expected).
• Withdrawal / coitus interruptus: Male partner withdraws his penis from the vagina just before ejaculation to avoid insemination.
• Lactational amenorrhoea (absence of menstruation): Based on the fact that ovulation, and therefore menstruation, do not occur during intense lactation following childbirth. Effective only up to the first six months after parturition; chances of failure rise thereafter.

(b) Barrier Methods

Ovum and sperms are prevented from meeting physically with the help of a barrier. Available for both males and females.

• Condoms: Made of thin rubber/latex sheath. Used to cover the penis in male (e.g., Nirodh) or vagina and cervix in female just before coitus, blocking entry of sperms. Disposable, self-fitted, no medical prescription needed; also protect from STDs and HIV.
• Diaphragms, cervical caps, vaults: Reusable rubber barriers inserted into the female reproductive tract to cover the cervix during coitus. Often used along with spermicidal creams, jellies and foams to enhance contraceptive efficacy.

(c) Intra-Uterine Devices (IUDs)

Inserted by a doctor or trained nurse into the uterus through the vagina. Among the most widely accepted reversible methods in India.

• Non-medicated IUDs: e.g. Lippes loop.
• Copper-releasing IUDs: CuT, Cu7, Multiload-375 — released Cu ions suppress sperm motility and the fertilising capacity of sperms.
• Hormone-releasing IUDs: Progestasert, LNG-20 — make the uterus unsuitable for implantation and the cervix hostile to the sperms.

(d) Oral Contraceptive Pills

Hormonal preparations (combinations of progestogens or progestogen–oestrogen) taken daily by females in the form of tablets — therefore called "the Pill". The pill is to be taken daily for 21 days starting preferably within the first 5 days of the menstrual cycle. After a gap of 7 days (during which menstruation occurs), it has to be repeated in the same pattern. They inhibit ovulation and implantation as well as alter the quality of cervical mucus to prevent / retard entry of sperms.

Saheli — a new oral contraceptive for the females containing a non-steroidal preparation — was developed by scientists at CDRI in Lucknow, India. It is a "once-a-week" pill with very few side-effects and high contraceptive value.

(e) Injectables & Implants

Progestogens alone or in combination with oestrogen can also be used by females as injections or implants placed under the skin. Their mode of action is similar to that of pills but their effective periods are much longer.

(f) Emergency Contraception

Administration of progestogens or progestogen-oestrogen combinations or IUDs within 72 hours of coitus have been found to be very effective as emergency contraceptives — useful in cases of accidental, unprotected intercourse or rape.

(g) Surgical Methods (Sterilisation)

Generally advised for the male/female partner as a terminal, highly-effective method to prevent any more pregnancies. They block gamete transport and thereby prevent conception.

• Vasectomy in male — small part of the vas deferens is cut or tied through a small incision on the scrotum.
• Tubectomy in female — small part of the fallopian tube is cut or tied through a small incision in the abdomen or via the vagina.

4.2.3 Comparison Table — Common Contraceptives

Worked Example 1 L2 Understand

Worked Example 2 L3 Apply