During the last century, especially in the last five decades, the rate of population growth is a cause of worry. In 2001, the population of India was 102.87 crores which has increased to 121.01 crores in 2011.

Reasons for population growth:

1. Immigration for trade, education or settling abroad.
2. Lower Death Rate: Two centuries ago the rate of population growth was less, since infant mortality rate and death rate of pregnant women, as well as death due to various deadly diseases, was high. Diseases like cholera, plague, TB (tuberculosis), typhoid, etc. were incurable. People succumbed to famines, etc.

Because the modes of transport and roads were improper, people could not get proper medical facilities. This scenario has completely changed today. Nutritious food is easily available, communicable diseases are under control due to advanced medical treatment and vaccination programmes. Pre-and-post-disaster management has improved and affected people are rehabilitated faster. So death rate has decreased whereas population growth rate has increased.

3. Increased Life-expectancy: Moreover, the standard of living has improved and so the average life span which Was about 40-41 years in 1920 has increased to 63-64 years. However, birth rate has not decreased noticeably. The factors responsible for increase in birth rate are: illiteracy, superstitions, orthodox thinking, social customs wherein a male child is considered important, child marriage, poverty, widow re-marriage, negative attitude towards the idea of a small family, etc.