India’s burgeoning population appears to be both a problem and an advantage. Very soon, the southern states may stare at an un-Indian situation: a shrinking populace, owing to a sharp dip in the fertility rate of women.

Analyzing the 2011 Census data, the Population Research Centre of the Bangalore-based Institute for Social and Economic Change found that many southern districts, a significant number of them in Karnataka, have recorded fertility rates lower than the national average. The study says turnaround will happen soon.

Half of India’s 1.21 billion population comprises women, and the national average fertility rate stands at 2.5, slightly higher than the targeted 2. The theory is simple: two children replace two parents, and the population remains stagnant.

Experts say women in most southern states appear to be settling for one child, pulling down the average fertility rate. Karnataka’s fertility rate stands at 2, but there’s also an interesting variation in the districts.

In Udupi, for instance, the fertility rate is 1.2; in Hassan, Mandya and Chikmagalur, it’s 1.4; in Dakshina Kannada and Kodagu, it’s 1.5. Bangalore, at 1.7, is well below the national average. Some districts, though, have high fertility rates: Bijapur stands at 3, and Bidar at 2.7.

The other South Indian states of Kerala, Andhra Pradesh and Tamil Nadu are in the sub-2 category.

“Women are, perhaps, postponing marriage and, subsequently, childbirth. Many are increasingly settling for one child as they are socially and biologically past their prime by the time they give birth for the first time,” said K S James, professor, Population Research Centre, who led the data analysis. What happens if the population shrinks? Arresting the spiralling population growth rate has always topped the nation’s agenda. Experts, though, beg to differ. A sudden turnaround in population could lead to demographic disarray, they say. “The first result of negative population growth is the number of elderly people goes up and young people comes down. This means there are fewer youngsters to take care of our elderly,” said Prof. K S James.

Experts say women make an informed choice to have a single child, given the high literacy level in the southern states.

“Often, this is to give the lone child a goodquality of life.Keeping in mind the high cost of living, young couples are increasingly settling for one child,” said retired ISEC professor KNM Raju.

With both men and women being educated, they make informed decisions. “The woman’s decision today is well thought out, and she has her partner’s support too,” said Raju.

The implication could be quite significant. If both partners in a marriage are themselves from single-child families, the responsibility of taking care of both sets of parents falls on them. “Parents these days are not dependent on their children financially. It’s the psychological dependence which will be missed the most,” Raju pointed out. Experts attribute this trend to the southern statesbeing open tochange. “It’s their willingness to accept social changes that work for them,” said Raju.

Unlike their southern counterparts,the northernstates are showing an increase in fertility rate. The country is evenly poised, with half the country adhering to the national average and below, and the other half exceeding the figure.