The relationship of birth weight with longitudinal changes in body composition in adult women.

Most research on birth weight and adult health status has reported adult measures at a single time point. This study examined the relationship of self-reported birth weight to longitudinal changes in adult body composition in 587 women of the Michigan Bone Health and Metabolism Study, followed from 1992 to 2007 and aged 24-50 years at baseline. Linear mixed models were used to estimate the association between three birth weight categories and women's 15-year changes in adult weight, height, BMI, waist and hip circumference, waist-to-hip ratio, and fat, lean, and skeletal muscle mass. Body composition measures increased in all women over the 15-year study period. At their adult baseline, high birth weight women weighed 13% more and had waist circumference and lean mass measures that were 5.51 cm and 3.91 kg larger, respectively, than normal birth weight women. No differences were observed in adult body composition between low and normal birth weight women and rates of change in the adult measures did not vary across the birth weight groups. Women heavier at birth continued to be heavier through adulthood, corroborating previous reports based on single measures of adult body composition. Research to address whether higher adult body composition in high birth weight women increases the longitudinal risk for obesity-related chronic diseases is needed.