Baby size link to health

STRONG evidence of a link between small size at birth and the risk of heart disease and stroke in later life has been uncovered by British scientists.

In one study aimed at exploring this link, researchers based at the Medical Research Council's environmental epidemiology unit, examined the medical records of more than 13,000 men born in Hertfordshire and Sheffield between 1907 and 1930. Death rates from heart disease and stroke were related to small size at birth. Researchers also found that increased risk of stroke was linked to low placental weight in relation to head size at birth. This growth pattern was found in babies born to mothers who had deformed pelvises caused by under-nutrition in childhood.

The MRC says these findings suggest that the origins of stroke may lie in poor nutrition during the mother's pregnancy which in turn prevents healthy development of the placenta.

In another study by the unit, a link between birth size and heart disease in a non-Western population was sought; 7,800 households in Mysore, South India were surveyed. This led to the identification of 517 people born in a hospital in the city between 1934 and 1954. The study showed that in this sample, smaller babies were about four times more likely to contract heart disease in later life than larger babies. Higher rates of heart disease were also found in babies whose mothers had low body weight during pregnancy.

The research, backed by the Wellcome Trust, could influence India's health policy. Coronary heart disease is predicted to outstrip infectious disease as the country's major killer by the year 2010. The scientists say improvements in the nutrition and health of young women may be needed. The results could also explain the high rates of heart disease in Indians living outside India.

David Barker, director of the MRC unit, says the Indian study reveals patterns of coronary disease similar to those in Britain: "They are not explained by adult lifestyle factors such as drinking, smoking, obesity and social class. They indicate that 'programming' within the womb as a result of fetal under-nutrition may be an important cause of cardiovascular disease. The findings on stroke tell us that for mothers, good nutrition is vital long before pregnancy."