India has one of the highest rates of birth defects in the world, with an estimated 61 to 70 affected births per 1,000 live births. With roughly 27 million children born each year, that translates to a staggering number of families affected annually. The reasons are not one single cause but a web of overlapping factors: widespread nutritional gaps, environmental contamination, cultural practices that increase genetic risk, limited prenatal screening, and the sheer scale of a population where most births occur in low-resource settings.
Nutritional Deficiencies and Neural Tube Defects
The single most preventable driver of birth defects in India is folic acid deficiency. When a woman doesn’t get enough of this B vitamin before and during early pregnancy, the baby’s brain and spinal cord can fail to close properly, leading to neural tube defects like spina bifida and anencephaly. In India, the rate of these defects is roughly 4 per 1,000 live births nationally, but in northern states it climbs as high as 7.5 per 1,000. For comparison, countries with mandatory folic acid fortification of flour (like the United States and Canada) have rates well below 1 per 1,000.
The Indian government provides iron and folic acid supplements through public health programs and has pushed for fortified foods in government-funded nutrition schemes. But supplementation during pregnancy often starts too late. Neural tube defects develop in the first few weeks after conception, often before a woman even knows she’s pregnant. Many public health experts have called for broader food fortification, similar to what dozens of other countries have adopted, so that women of reproductive age are protected before pregnancy begins rather than after the first prenatal visit.
Beyond folic acid, widespread deficiencies in iron, vitamin B12, and other micronutrients compound the problem. Vegetarian diets, common across much of India, can be low in B12 unless carefully supplemented. Chronic anemia affects a large share of Indian women during their childbearing years, creating a baseline of nutritional stress that raises the odds of developmental problems during pregnancy.
Consanguineous Marriage and Genetic Risk
In parts of southern and central India, marriage between close relatives, particularly between first cousins, remains culturally common. These consanguineous marriages are driven by longstanding customs around family bonds, community identity, and socioeconomic factors. The genetic consequence is significant: children born to consanguineous parents are roughly 2.5 times more likely to have congenital malformations than children of unrelated parents.
The reason is straightforward. When both parents share recent ancestors, there’s a much higher chance that both carry the same copy of a harmful recessive gene. A child who inherits that gene from both sides will express the disorder, whether it’s a heart defect, a metabolic condition, or a structural abnormality. In populations where consanguinity is practiced across multiple generations, these risks accumulate. While the practice has declined in many parts of the world, it persists in significant portions of India due to deep cultural roots and limited genetic counseling infrastructure.
Environmental Contamination
Millions of people in India drink groundwater contaminated with arsenic, particularly in West Bengal, Bihar, Uttar Pradesh, and parts of the northeast. Research has found a clear link between arsenic in drinking water and congenital anomalies. Women exposed to arsenic concentrations above 10 micrograms per liter during pregnancy face elevated risk of having babies with heart defects. For every additional microgram per liter of arsenic in household water, placental arsenic deposits increase by about 2.1%, meaning the toxin reaches the developing baby directly.
Arsenic exposure during pregnancy also raises the risk of gestational diabetes, anemia, low birth weight, and miscarriage. Female babies appear to be especially vulnerable, with higher rates of both low birth weight and congenital cardiac anomalies.
Pesticide exposure adds another layer of risk. India is one of the world’s largest users of agricultural chemicals, and in heavy farming regions like Punjab, families living near treated fields face significant exposure. Studies have linked occupational and residential pesticide exposure to neural tube defects, limb reduction defects, and musculoskeletal abnormalities in newborns. Mothers exposed to certain persistent pesticides (including compounds related to DDT) had over 11 times the odds of delivering a baby with a neural tube defect compared to unexposed mothers. Living closer to high-use agricultural areas, conceiving during spring application season, and direct occupational handling of pesticides all increase risk.
Gaps in Prenatal Screening
Early detection doesn’t prevent birth defects, but it allows families and doctors to prepare, intervene when possible, and in some cases pursue corrective surgery shortly after birth. In high-income countries, nearly all pregnant women receive a detailed anatomy scan around 18 to 20 weeks, along with first-trimester screening for chromosomal conditions. In much of rural India, access to quality ultrasound during the right window remains inconsistent.
India launched the Rashtriya Bal Swasthya Karyakram (RBSK) in 2013, a national program to screen children from birth through age 18 for conditions including neural tube defects, Down syndrome, cleft lip and palate, club foot, congenital heart disease, hip dysplasia, congenital cataracts, and congenital deafness. Between 2013 and 2023, the program screened over 157 million children. In the pre-COVID window of 2018 to 2020 alone, more than 21 million newborns were screened.
The program’s reach is impressive, but a critical gap remains: disaggregated data on what types of defects are being found, and at what rates, has not been made publicly available. Without that information, it’s difficult to target prevention efforts or measure whether policies are actually reducing the burden. India still lacks a comprehensive, nationwide birth defect surveillance system comparable to those in the U.S. or Europe, making it hard to know the true scope of the problem in many states.
Gestational Diabetes and Maternal Health
Gestational diabetes, which develops during pregnancy and causes persistently high blood sugar, is a known risk factor for congenital heart defects and other structural abnormalities. A large study of pregnant women from lower and middle socioeconomic backgrounds in Delhi found that a substantial proportion developed gestational diabetes, with risk rising about 10% for each additional year of maternal age. Higher body weight and pre-existing blood sugar issues before pregnancy were also independent risk factors.
India is in the middle of a diabetes epidemic more broadly, and the metabolic conditions that drive gestational diabetes, including insulin resistance and obesity, are becoming more common among younger women. When gestational diabetes goes undiagnosed or poorly managed, the developing baby is exposed to elevated blood sugar during critical periods of organ formation, raising the likelihood of heart and other defects.
Scale, Poverty, and Compounding Risks
What makes India’s birth defect burden so large is not any single factor but the way these risks stack on top of each other in a population of 1.4 billion people. A woman in a rural farming community might simultaneously be folic acid deficient, exposed to pesticides, drinking arsenic-laced water, and unable to access prenatal care until well into her second trimester. Each of those factors independently raises risk. Together, they multiply it.
Globally, 94% of births with serious defects occur in low- and middle-income countries. India, as the world’s most populous nation with vast regional differences in healthcare, nutrition, and environmental quality, accounts for a disproportionate share. The tools to reduce this burden exist: food fortification, genetic counseling, clean water infrastructure, pesticide regulation, and universal early prenatal screening. The challenge is deploying them at scale across a country where the most vulnerable communities are often the hardest to reach.