Fertility rates in India are more closely related to education levels and the socio-economic development within a state, than to religious beliefs, according to an IndiaSpend analysis of government data and research evidence.

The evidence IndiaSpend looked at shows that richer families and states with better health facilities and higher female literacy have lower fertility rates in India. Globally, there is little evidence to link religion and fertility rates, with poorer, conflict-ridden states and countries with lower female empowerment reporting higher population growth rates.

When the office of the Registrar General and Census Commissioner of India released fertility rates for the Indian population last year, the conversation was hijacked by the difference in population growth rates across religions. Several newspapers emphasised that the data showed that Muslim women had higher fertility rates than non-Muslims, and that the percentage of Muslims in the population was steadily growing.

The numbers showed that the proportion of Muslims in India had grown to 14.2% of the total population in 2011, up from 13.4% in 2001, while the proportion of Hindus had reduced to 79.8% from 80.5%. The percentage of Christians and Jains did not significantly change at 2.3% and 0.4%, respectively, while the proportion of Buddhists decreased from 0.8% to 0.7%, and that of Sikhs reduced from 1.9% to 1.7%.

This implicit suggestion that Muslims have more children than other religious communities, missed data that shows how population growth rates and the total fertility rate – or the average number of children a woman has over her childbearing years – vary widely between India’s states. The total fertility rate seems more closely related to per-capita income, healthcare and other basic facilities in that state.

Development and fertility

Compare, for instance, Kerala and Uttar Pradesh. In 2011, the total fertility rate of Uttar Pradesh, at 3.3, was higher than the Indian average of 2.4, and higher than the rate in Kerala, at 1.8, according to census data.

The Muslim population in Uttar Pradesh increased 25.19%, while the Muslim population in Kerala increased 12.83% between 2001 and 2011. Over the same period, the Hindu population increased 18.9% in Uttar Pradesh and 2.8% in Kerala.

The higher growth rates of Muslims in northern states are “more or less part of a northern culture than a Muslim culture”, NC Saxena, the former secretary of the Planning Commission of India, said in an interview to The Wire, a nonprofit journalism portal.

This is in sync with higher average total fertility rates in northern and central states, such as Uttar Pradesh (3.3), Bihar (3.5), Chhattisgarh (2.7), and Madhya Pradesh (2.9), as compared to southern states like Andhra Pradesh (1.8), Karnataka (1.9), Kerala (1.8), and Tamil Nadu (1.7), according to 2011 census data.

The states with the highest fertility rates in India are all in north and central India – Bihar, Uttar Pradesh, Madhya Pradesh, Rajasthan (which has a total fertility rate of 2.9), Jharkhand (2.8), and Chhattisgarh.

These overall fertility rates seem more related to the state’s development. For instance, Kerala has a literacy rate of 93.9%, compared to 69.7% in Uttar Pradesh in 2011. In the same year, 99.7% of mothers in Kerala received medical attention at delivery compared to 48.4% of mothers in Uttar Pradesh. 74.9% of women were above the age of 21 in Kerala at marriage, compared to only 47.6% in Uttar Pradesh.

Another way to interpret population growth rates is through the difference in poor and rich states. Empowered Action Group states, which include the poorest in India – Rajasthan, Uttar Pradesh, Uttarakhand, Bihar, Jharkhand, Madhya Pradesh, and Chhattisgarh – have higher population growth. Between 2001 and 2011, the population of Empowered Action Group states grew at a rate of 21%, compared to 15% for the rest of India. Still, decadal population growth rates even in these states has fallen when compared to the decadal growth rate of 24.99% between 1991 and 2001.

Differences within states

Still, there are differences within states in total fertility rates between religious groups. In 2005-2006, according to data from the third National Family Health Survey, Uttar Pradesh had a total fertility rate of 3.3, higher than the all-India average of 2.4.

Kerala had a total fertility rate of 1.93. In 2005-2006, Muslims in Kerala had a total fertility rate of 2.46, higher than that of Hindus in Kerala, at 1.53. But the Muslim total fertility rate in Kerala was lower than that of Hindus in Uttar Pradesh, at 3.73. The total fertility rate of Muslims in UP was 4.33.

One reason for the higher Muslim fertility within a state could be wealth-related factors.

Survey information showed that families in the lower wealth quintiles have more children than richer families. For instance, in Bihar, women in the lowest wealth quintile have a total fertility rate of 5.08, while women in the highest quintile have a total fertility rate of 2.12. The same holds true for a richer state, like Maharashtra, where the lowest wealth quintile has a total fertility rate of 2.78, compared to the richest wealth quintile with a total fertility rate of 1.74.

On average, Muslims across India are poorer than Hindus across India, with an average monthly household per capita expenditure of Rs 833, compared to Rs 888 for Hindus, Rs 1,296 for Christians and Rs 1,498 for Sikhs, according to a 2013 National Sample Survey report, based on data from 2009-2010.

Researcher Sriya Iyer, a professor at the University of Cambridge, said that religion does not have a statistically significant effect on fertility if other factors such as “access to education (quantity and quality), income, whether couples have help with childcare or not, local health care provision (quantity and quality) that lowers infant mortality and hence increases child survival, and the degree of urbanisation of the community” are taken into account.

Further, her 2002 study in a Karnataka taluka (an administrative sub-division of a district) found that both Hindus and Muslims had more children than Christians, but she argued that religion affects fertility and contraception through other socio-economic factors, such as a family’s decision to educate its children, rather than through the ideological tenets of a religion.

Socio-economic factors affect the fertility of religious groups in different ways. For instance, higher education for women, and secondary education for men, lowers the fertility of Muslims but not of Hindus or Christians, the study reported, suggesting that family planning programs might have to be designed keeping in mind these differences.

Further, Iyer said, evidence from India showed that, over the long term, “total fertility rate between religious groups are projected to converge, as women from all religious communities are having fewer children today than their mothers or grandmothers”.

Religion and fertility

There is little evidence internationally of the correlation between religion and fertility rates.

For instance, according to World Bank data, in 2014, Bangladesh, India’s Muslim-majority neighbor, had a total fertlity rate of 2.2. Iran, another Muslim country, has a total fertility rate of 1.7, below replacement level, which means the current population cannot be replaced at the prevailing population growth rate.

Similarly, Malaysia and Indonesia, both Muslim-majority countries, have fertility rates of 1.9 and 2.5, respectively. Other Muslim-majority countries, such as Saudi Arabia (2.8), and Egypt (3.3), have higher fertility rates. The Hindu and the Muslim populations in Pakistan have the same total fertility rate – 3.2 – according to data from the Pew Research Center.

Another neighboring country, Sri Lanka, with a Buddhist majority, had a total fertility rate of 2.1 in 2014. Its Buddhist population had a total fertility rate of 2.2 between 2010 and 2015, while both Hindus and Muslims had a higher total fertility rate, at 2.3 and 2.8, respectively.

Socio-economic factors

Fertility rates also depend on a number of factors unrelated to religious group. For instance, socio-economic factors, education, modernisation, access to contraceptives, and state policies for development, all affect fertility, according to P Arokiasamy, the head of the department of development studies, at Mumbai-based International Institute for Population Sciences.

In addition, population growth rates also depend on other factors such as work opportunities for women, access to contraception, age at marriage, and decision-making power within the household. For instance, a meta-analysis of studies, published in 2014, found a positive correlation between women’s empowerment and lower fertility, longer birth intervals, and lower rates of unintended pregnancy.

Population growth

Population projections by the Pew Research Center, a US-based think tank, estimates that by the year 2050, Muslims will make up 18.4% of India’s population, the largest population of Muslims in any county in the world. But India’s Hindu population will still be larger than the total Muslim population of India, Pakistan, Indonesia, Nigeria, and Bangladesh, five countries with the largest Muslim population in the world.

Overall, population growth is slowing down in India and the decadal growth rate fell from 21.54% between 1991 and 2001 to 17.64% between 2001 and 2011, which is in line with global trends that show that population growth rates fall as a country becomes more developed and literate.

In India, the Muslim growth rate is falling faster than the growth rate of Hindus.

The decadal population growth rate of Muslims fell 4.9 percentage points from 29.5% in 2001 to 24.6% in 2011, while that of Hindus fell 3.5 percentage points, from 20.3% to 16.8%. In 2001, 65.1% of all Hindus, above the age of 7 years, were literate, while 59.1% of Muslims were literate, according to census data. In 2011, the percentage of literate Hindus rose to 73.3%, while that of Muslims increased to 68.5%.

Fertility rates of populations that have higher fertility, such as low-income families and Muslims, are falling faster than other groups, as methods of contraception and education spread to these groups, explained Arokiasamy of International Institute for Population Sciences.

This article first appeared on IndiaSpend, a data-driven and public-interest journalism non-profit.