Abstract: | Background: Small body size at birth and during infancy is associated with an increased risk of adult osteoporosis and cardiovascular disease. Fetal programming of the growth hormone–insulin‐like growth factor (GH‐IGF) axis may provide a mechanism for these epidemiological findings. Aims: To determine whether measurements of GH and IGF‐I in late middle age were related to size at birth and in infancy. Methods: Overnight urinary GH excretion and fasting serum IGF‐I were measured in 309 men and 193 women from Hertfordshire (born 1920–1930) for whom birthweight and weight at 1 year were recorded. Serum IGF‐I was measured in men and women from Preston (n = 254, born 1935–1943) and Sheffield (n = 215, born 1939–1940) whose birthweight and other birth measurements were recorded. Results: Urinary GH and serum IGF‐I were not related to birthweight, other measurements at birth, or weight at 1 year. Conclusion: In contrast to previous studies in children or young adults, these data do not support the hypothesis that IGF‐I concentrations are programmed by intra‐uterine events, as assessed by birthweight, in late middle age. |