Advancing maternal age is associated with lower bone mineral density in young adult male offspring

Advancing maternal age has been related to increased risk of fetal death and morbidity, as well as higher fracture risk during childhood, in the offspring. In the present study, we demonstrate that advancing maternal age is independently associated with reduced bone mass in the young adult male offspring. In Sweden the maternal age in both primi- and multipara mothers has steadily increased during the last three decades. It has been previously reported that advancing maternal age increases the risk of fetal death, but also of morbidity in the offspring, such as chromosome abnormalities, leukemia, diabetes mellitus type 1, and schizophrenia. Whether or not maternal age influences peak bone mass has not been reported. The aim of the present study was to investigate whether a high maternal age was associated with lower peak bone mass, as measured using DXA in a large cohort of male offspring [the Gothenburg Osteoporosis and Obesity Determinants study (GOOD)]. Through the Swedish multi-generation register, we identified the mothers of 1,009 GOOD study subjects. From the Swedish medical birth register detailed information about the medical circumstances at the time of child birth were obtained, including maternal and offspring anthropometrics (birth height and weight), maternal age, and smoking habits, parity and length of pregnancy. Maternal age was inversely correlated to areal BMD (aBMD) at the total body (r =-0.07, p = 0.03) and the lumbar spine (r =-0.09, p < 0.01). Using a linear regression model (with covariates including current physical activity, smoking, calcium intake, weight, present height and birth height, total body lean and fat mass in the offspring, and length of pregnancy), we found that maternal age negatively independently predicted lumbar spine aBMD (beta =-0.08, p < 0.01) in the male offspring. In conclusion, our results suggest that advancing maternal age could negatively affect bone mass in young adult men.