The science which deals with the study of population is called demography. The theory of demographic transition throws light on changes in the birth rate and death rate and consequently the growth of population. According to this theory, there are certain stages of population development and every country has to pass through these stages. This theory was propounded by W.S. Thompson and F.W. Notestein. According to the demographic thoughts or demographers generally there a re three stages of population growth These are first stage ( High birth and high death rate), second stage (Low birth rate and low death rate) and the third stage (High birth rate and low death rate).
State 1 – (High Birth Rate and High Death Rate) :
It is the preliminary stage of an economy when a country has an agrarian economy and low level of income there is high birth rate and high death rate. This stage is purely an underdeveloped stage of an economy and the growth of population is very low. The birth rate is high due to universal and early marriage, widespread poverty, prevalence of illiteracy, traditional social beliefs and customs, attitude towards male child, absence of knowledge about family planning techniques, joint family system etc. Again due to high mortality rate people wanted to have more children. Thus, in this stage birth rate are high out of economic requirements.
In this stage, the death rate is also high due to insufficient food and absence of adequate medical and sanitation facilities. Excepted this high death rate is associated with the factors like epidemic and it is deadly disaster and frequent occurrences of natural calamities. So in this stage, birth rate is high. So in this stage birth rate and death rate are equal.
Stage – II (High Birth Rate and Low Death Rate) :
When the economy development started the death rate falls rapidly but the birth rate falls slowly or remains stable. This leads to widening the gap between birth rate and death rate. There is high birth rate due to universal and early marriage, widespread poverty, illiteracy, ignorance, superstitions, joint family system, attitude towards make child, unavailability of family planning techniques etc. So in this stage, the growth rate of population becomes very high.
In the second stage of demography transition, the rapid decline of death rate is caused by the direct and indirect effect of economic development such as better and adequate food, proper housing, pure drinking water, better medical facilities, better sanitation, development of antibiotics, vaccines and introduction of immunization programmes. Decline in the infant mortality rate also causes decline in the death rate.
This is crucial or dangerous stage which causes population explosion. India is still in the second stage of demographic transition. The birth rate in 1991 was 909 per thousand and the death rate was 10 per thousand and the birth rate in 2000 was 25.8 and the death rate was 8.5 per thousand. So the birth rate in 1998 was 97 per 1000. So the birth rate is more compared to the death rate. The infant mortality rate in 1998 was 97 per thousand which decreases to 69 per thousand in the year of 2000. It causes decline in the death rate.
Stage – III ( Low Birth Rate and Low Death Rate) :
The third stage of demographic transition is characterized by a low birth rate and low death rate leading to a stable population growth. Due to the development and consciousness of parents both death rate and birth rate become very low. More industrialization and urbanization with preference of small families also reduces the birth rate and death rate. General consciousness in the minds of the people about the bad effects of population growth leads to acceptance of family planning techniques.
In respect of India’s demographic transition it is found that up to 1921 India was in the second stage and remains in till now.