Population explosion

Better health facilities and living conditions in the last century made the population grow explosively.

World population: about 2 billion in 1900; roughly 6 billion by the year 2000; 7.2 billion in 2011.

India: about 350 million at Independence, close to 1 billion by 2000, and past 1.2 billion in May 2011.

Probable reasons: a rapid fall in the death rate, the maternal mortality rate (MMR) and the infant mortality rate (IMR), and a rise in the number of people of reproducible age.

The RCH programme lowered the growth rate only marginally. The 2011 census put it below 2 per cent, that is 20 per 1000 per year, which can still make the population rise fast and threaten food, shelter and clothing.

Measures taken: motivating small families with contraceptives (the 'Hum Do Hamare Do' slogan; some young urban working couples follow a one-child norm), raising the legal marriageable age to 18 years for females and 21 years for males, and incentives for couples with small families.

An ideal contraceptive is easy to use and to obtain, effective, reversible, has few or no side effects, and leaves sexual drive, desire and the sexual act untouched.

Contraceptive methods fall into seven groups: natural (traditional) methods, barriers, IUDs, oral pills, injectables, implants and surgical methods.