Overpopulation can result from an increase in births, a decline in mortality rates due to medical advances, from an increase in immigration, or from an unsustainable biome and depletion of resources.
It is possible for very sparsely- populated areas to be overpopulated, as the area in question may have a meager or non-existent capability to sustain human life e.g. Clean water, clean air, food, shelter, warmth and other resources necessary to sustain life need to be considered while evaluating the extent of overpopulation.
However, in the real world the answer is never really simple or definite.
One must always consider the political, social and economic consequences of population control.
In India, the government introduced Nirodh, a contraception to control child birth.
It coined a slogan “Hum do, hamare do” implying one family, two children to reinforce the message of population control.
Rockefeller, Frederick Osborn (1952), and Isaac Asimov.
In the past, there have also been opposition to population control policies.
Population control has been necessitated by a concept of overpopulation, a condition which does not depend only on the size or density of the population, but on the ratio of population to available sustainable resources.
It also depends on the way resources are used and distributed throughout the population.