Falling fertility rate will have a direct impact on the child sex ratio in India irrespective of the methods of population control.

The decline of family sizes in India—with richer, healthier and better-educated families deciding to
have fewer children—has gone hand in hand with a worsening of the sex ratio.
The decline in fertility explains one-third to one-half of the recent increase in India’s sex ratio in
favor of boys.
Data from the National Family Health Survey (NFHS) 2015-16 indicates that families where a son is
born are more likely to stop having children than families where a girl is born.
The male-biased Indian sex ratio at birth is distinctly sharpened for the last child of the family.
According to a comparison made in the 2017-18 Economic Survey with Indonesia, sex ratios in a
population do not normally change significantly with birth order, signaling that there is something
“unnatural” going on with Indian fertility.
Role of in-utero selection procedures-
Although, families that continue to have children until they have as many sons as they would like.
However, in-utero sex selection definitely plays a part, too.
With the spread of ultrasound technology that can be used for prenatal sex determination, the
likelihood that third and fourth order births would be girls in families that had not yet had a son
declined sharply after the mid-1980s.
By the mid-1990s, ultrasound access was more widespread, but the desire for small families was
growing, too. As a result of these two phenomena, families were no longer waiting for third and
fourth births to intervene and even second order births began to be less likely to be those of girls.
Observations across states and countries-
According to Chinese census data, it was found that areas in China that enforced fines for second
births more strictly during the one-child policy regime had lower fertility but worse sex ratios than
areas that enforced fines less strictly.
A scheme launched by the Haryana government in 2002 offered financial incentives to families that
had fewer children, with the highest cash incentive to those having only one daughter, and a lower
amount to those having only one son, or only two daughters. The result was a decline in fertility as
evidenced by the share of families with only one child but it was driven almost entirely by families
having only one boy.
There was no increase in families having only one daughter, despite the financial incentives being
highest for this outcome.
Starting with Rajasthan in 1992, several states began to enact laws debarring candidates with more
than two children from contesting local body elections. The laws did reduce fertility, but this came
at the cost of a worsening sex ratio, as families tried to ensure their future eligibility for public
office, while still having their desired number of sons.
Conclusion-
Population control schemes will only seek to worsen the sex ratio, even as growth and development
are already lowering fertility, making the task of “Beti Bechao” more challenging than it is today.