Muslims in India have a much higher total fertility rate (TFR) compared to that of other religious communities in the country. Because of higher birthrates and an influx of migrants from neighboring Bangladesh, the percentage of Muslims in India has risen from about 10% in 1991 to 13% in 2001.The Muslim population growth rate is higher by more than 10% of the total growth compared to that of Hindus. However, since 1991, the largest decline in fertility rates among all religious groups in India has occurred among Muslims.
Demographers have put forward several factors behind high birthrates among Muslims in India. According to sociologists Roger and Patricia Jeffery, socio-economic conditions rather than religious determinism is the main reason for higher Muslim birthrates. Indian Muslims are poorer and less educated compared to their Hindu counterparts. Noted Indian sociologist, B.K. Prasad, argues that since India's Muslim population is more urban compared to their Hindu counterparts, infant mortality rates among Muslims is about 12% lower than those among Hindus.
However, other sociologists point out those religious factors can explain high Muslim birthrates. Surveys indicate that Muslims in India have been relatively less willing to adopt family planning measures and that Muslim women have a larger fertility period since they get married at a much younger age compared to Hindu women.
A study conducted by K.C. Zacharia in Kerala in 1983 revealed that on average, the number of children born to a Muslim woman was 4.1 while a Hindu woman gave birth to only 2.9 children. Religious customs and marriage practices were cited as some of the reasons behind the high Muslim birth rate.According to Paul Kurtz, Muslims in India are much more resistant to modern contraception than are Hindus and, as a consequence, the decline in fertility rate among Hindu women is much higher compared to that of Muslim women.
The National Family and Health survey conducted in 1998–99 highlighted that Indian Muslim couples consider a substantially higher number of children to be ideal for a family as compared to Hindu couples in India.The same survey also pointed out that percentage of couples actively using family planning measures was more than 49 percent among Hindus against 37 percent among Muslims.A 1996 survey conducted in the Lucknow district revealed that 34 percent of the Muslim women believed that family planning went against dictates of their religion while none of the Hindu women surveyed believed that religion was a barrier against family planning.
According to a 2006 committee appointed by the Indian Prime Minister, by the end of the 21st century India's Muslim population will reach 320 to 340 million people (or 18% of India's total projected population). Swapan Dasgupta, a prominent Indian journalist, has raised concerns that the higher Muslim population growth rate in India could adversely affect the country's social harmony. Phillip Longman, a renowned demographer, remarked that the substantial difference between Muslim and Hindu birthrates could contribute to ethnic tension in India.