47 Percent of India's Low-Birthweight Babies Born in These Four States: BMJ Study Shows - Video

Despite significant progress in reducing low birthweight cases across India over the past three decades, Uttar Pradesh, Bihar, Maharashtra, and West Bengal continue to report alarmingly high numbers, reveals new research published in the open-access journal BMJ Global Health.

Low birthweight- defined as a newborn weighing less than 2500 grams- is considered a key indicator of maternal health, nutrition, and future health outcomes for the child, including cognitive development and the risk of chronic diseases.

To assess trends over the past 30 years, researchers analyzed data from five rounds of the National Family Health Survey (NFHS), covering the period from 1992–93 to 2019–21. The study included 626,087 live births, with 440,200 (around 70%) having recorded birthweights, and 614,428 (98%) assessed by the mother for perceived birth size. The proportion of babies with recorded weights rose from 16% in 1993 to 90% in 2021, improving the data's reliability over time.

Nationally, low birthweight prevalence dropped from 26% in 1993 to 18% in 2021, with the state-level average falling from 25% to 16%. Rajasthan (48%) and Chhattisgarh (42%) had the highest prevalence in 1993, while in 2021, Punjab and Delhi led with 22%. In contrast, Mizoram consistently reported the lowest rates- 6% in 1993 and 4% in 2021.

The latest NFHS data from 2019–21 estimates 4.2 million low birthweight babies in a single year, with nearly 47% born in Uttar Pradesh, Bihar, Maharashtra, and West Bengal. Similarly, 2.5 million babies were reported to be of smaller-than-average size by their mothers, half of them in the same four states.

“Low birth weight is likely to be more prevalent among non-weighed children since weighing correlates strongly with healthcare infrastructure and being born in a health facility. Also, low socioeconomic status is linked to both lack of access to healthcare and low birth weight,” the researchers explained.

Reference: Omar Karlsson, Akhil Kumar, Rockli Kim, SV Subramanian - Trends in low birth weight across 36 states and union territories in India, 1993-2021: BMJ Global Health 2025;10:e016732.