A groundbreaking three-decade-long study from Pune has fundamentally challenged the medical understanding of gestational diabetes, revealing it is not a temporary condition of pregnancy but the visible tip of a lifelong metabolic disorder that begins in childhood, fueled by poor nutrition.
The Intergenerational Chain of Risk
The research, known as the Pune Maternal Nutrition Study, began in 1993 across six villages in Pune district. It meticulously tracked families to understand the evolution of diabetes in Indians. The story of Sonabai and her daughter Maina, study participants, illustrates a silent crisis. Sonabai, despite a life of hard physical labour, had a poor diet. Years of undernutrition impaired her pancreas, leading to insulin deficiency and elevated blood sugar, even without obesity.
Her daughter, Maina, born small at 2.5 kg, grew up on fried, processed foods and potato chips. By age six, her blood sugar levels were already high. When Maina became a mother at 18 in 2020, she developed gestational diabetes. Managed through diet, she delivered a baby. Alarmingly, by age five, Maina's own daughter had developed severe glucose intolerance, highlighting a rapid intergenerational transmission of diabetes risk.
Findings Overturn Conventional Wisdom
Published in the journal Diabetologia, the study by researchers from KEM Hospital and Research Centre analysed data from about 800 women who delivered babies between 1994 and 1996. The key finding is that high blood sugar during pregnancy reflects persistently higher glucose levels since childhood and puberty, not merely a reaction to pregnancy hormones.
Women in the highest quartile for blood glucose during pregnancy were found to have had higher levels long before conception, indicated by elevated pre-pregnancy HbA1c. The study quantified this risk: high childhood glucose levels doubled the odds of high glucose during pregnancy and increased the post-delivery risk five-fold.
"Our findings suggest that high blood glucose in pregnancy is not a new condition caused by pregnancy but part of a life-long pattern," stated Dr. Chittaranjan Yajnik, lead author and founder director of the Diabetes Unit at KEM Hospital Research.
A Call for Early Intervention and Indian-Specific Guidelines
The study strongly supports the Developmental Origins of Health and Disease (DOHaD) theory. It posits that poor foetal nutrition and being born small 'program' the body for insulin resistance. When combined with a calorie-dense modern diet and rapid weight gain later, the risk of diabetes, hypertension, and heart disease skyrockets.
Dr. Yajnik argues this reveals a critical missed window in current healthcare. "The most critical window for intergenerational programming of diabetes lies before and around conception," he explains. Current practice, which diagnoses gestational diabetes only after pregnancy is established, often after 20 weeks, is too late.
The researchers urge a paradigm shift. They call for tracking metabolism and prioritising the health of girls and young women much earlier. They also emphasise that Indian babies are among the smallest globally, yet management guidelines are based on Western data. The team advocates for national studies tailored to Indian realities to develop customised prevention strategies.
"Improving the health of young girls will help reduce the rapidly growing epidemic of these diseases in India," Dr. Yajnik concluded, framing the findings not just as a medical insight but as a urgent public health imperative for the nation.
