BackgroundMany studies have shown that low birth weight is associated with high blood pressure. The composition of the diet of pregnant women has also been found to affect blood pressure in their children. We assessed the effect of prenatal exposure to the Dutch famine of 1944–1945, during which the caloric intake from protein, fat and carbohydrate was proportionally reduced, on blood pressures in adults now aged about 50 years.Methods and resultsWe measured blood pressures at home and in the clinic among people born at term in one hospital in Amsterdam, The Netherlands, between November 1 1943 and February 28 1947, for whom we had detailed birth records. Blood pressures of people exposed to famine during late (n= 120), mid-(n= 109) or early gestation (n= 68) were compared with those of people born in the year before or conceived in the year after the famine (unexposed subjects,n= 442). No effect of prenatal exposure on systolic and diastolic blood pressure was observed. The mean systolic blood pressure taken in the clinic in those exposed in late gestation, and adjusted for sex and age, was 1.3 mmHg higher than in the unexposed group (95% confidence interval −1.9 to 4.4). The mean systolic blood pressure differed by −0.6 mmHg (95% confidence interval −3.9 to 2.7) for those exposed in mid-gestation and −1.7 mmHg (95% confidence interval −5.6 to 2.2) for those exposed in early gestation. People who were small at birth had higher blood pressures. A 1 kg increase in birth weight was associated with a decrease of 2.7 mmHg (95% confidence interval 0.3 to 5.1) in systolic blood pressure. Analyses of blood pressures measured at home gave similar results.ConclusionHigh blood pressure was not linked to prenatal exposure to a balanced reduction of macronutrients in the maternal diet. However, it was linked to reduced fetal growth. We postulate that it might be the composition rather than the quantity of a pregnant woman's diet that affects her child's blood pressure in later life.