A widely used measure of fertility levels is the ‘total fertility rate’, or the average number of children a woman will have in her lifetime. (Subrata Biswas/Hindustan Times)
A widely used measure of fertility levels is the ‘total fertility rate’, or the average number of children a woman will have in her lifetime. (Subrata Biswas/Hindustan Times)

What a narrowing Hindu-Muslim fertility gap tells us

3 mKartik Kwatra , 

After nearly 40 years, fertility gap between the two communities has started reducing. It’s another reason why their population shares won’t change radically

TopicsPlain Facts

The fact that a Muslim household in India, on average, gives birth to more children than a Hindu household is used to peddle fiction of many kinds. One of this is fear-mongering that higher fertility among Muslims can sizeably increase their share in India’s population—and bring down the share of Hindus.

New evidence from the latest National Family Health Survey (NFHS), conducted in 2015-16, suggests that such fear-mongering is without any basis. The survey data shows that the fertility gap between Hindus and Muslims has narrowed for the first time in many decades.

A widely used measure of fertility levels is the ‘total fertility rate’, or the average number of children a woman will have in her lifetime. According to the 2005-06 NFHS, this figure was 3.4 children for Muslims and 2.6 children for Hindus, or a fertility gap of 30.8%. Latest NFHS data shows that this gap has narrowed to 23.8% in 2015-16, a difference of half a birth on average per woman, even as both communities are having fewer children than before.

It’s after nearly 40 years that the fertility gap between the two communities has started narrowing. At the time of independence, Muslim fertility exceeded Hindu fertility by about 10%. The differential started increasing during the 1970s, primarily due to higher adoption of contraception by Hindus. It continued in that direction till the 1990s, crossing 30%.

Census 1991 data shows this divergence. Chart 2A shows child births to Muslim women as a ratio of child births to Hindu women for various age bands above 40 years (who have completed their reproductive cycle). A ratio of 1 indicates parity, and above 1 indicates higher Muslim births. The mark-up over 1 is the fertility gap; for example, a reading of 1.25 indicates the fertility rate of Muslims is 25% higher than that of Hindus.

As one moves from women aged 65+ years to younger women aged 40-44 years, the ratio increases from 1.11 to 1.25, indicating higher Muslim births in the younger cohorts. This was chiefly due to the difference in contraceptive usage between Hindus and Muslims in 1970s. The differential was much lower for women aged 65+ years in 1991 for both communities as they completed their reproductive cycle by 1970s.

Demographic transition—a process of sustained decline in fertility levels, enabled by the family planning programme, starting in 1970s in India—led to this divergence. Urban areas led rural areas in fertility transition. As a result, Hindu-Muslim fertility differential in urban areas was much higher in 1991.

Both Census 2011 and NFHS show the fertility differential stabilised at around 30%. In 2011, as one moved from women aged 55-59 years (women who had completed their reproductive cycle by 1991) to women aged 45-49 years (who had completed their reproductive cycle by 2001), unlike 1991, the above-mentioned ratio stayed in a narrow range of 1.31-1.34—or a 31-34% fertility gap.

Other factors that affect fertility such as poverty don’t fully explain the relatively higher fertility of Muslims. Chart 3 plots the average household size of population segments that form the bottom 10%, 20%, 30% to 100% of population by levels of consumption expenditure for both religions, based on data from a 1993-94 NSSO report. The average household size in each percentile class was higher for Muslims.

This gap remains, but it is now narrowing. In a demographic transition, this gap between the leader (Hindus) and the laggard (Muslims) increases initially—until the leader reaches a stable value. This is usually the ‘replacement fertility level’, or the fertility level at which the population exactly replaces itself. In India, it is considered to be 2.1 children per woman.

Thus, even when Muslim fertility is declining, the fertility gap would not narrow until the Hindu fertility level stabilizes. Since NFHS-4 data suggests that Hindus have now achieved replacement fertility, and the Hindu-Muslim fertility gap has reduced by 7 percentage points, a further narrowing of in the fertility gap is expected in Census 2021.

The late demographer P.N. Mari Bhat had projected that Hindus will achieve replacement fertility by 2021 and a stable population by 2061; Muslims will achieve replacement fertility by 2031 and population stabilization by 2101, and will account for 18.8% of India’s population then. Bhat’s 2011 projections are extremely close to Census 2011 figures. But even if his projections miss the mark by a long way, the idea that higher Muslim fertility will lead to Hindus becoming a minority in India will still remain a red herring.