Fetal and infant growth predict hip geometry at 6 y old: findings from the Southampton Women's Survey.
Harvey NC., Cole ZA., Crozier SR., Ntani G., Mahon PA., Robinson SM., Inskip HM., Godfrey KM., Dennison EM., Cooper C., Southampton Women's Survey Study Group None.
BACKGROUND: We investigated relationships between early growth and proximal femoral geometry at age 6 y in a prospective population-based cohort, the Southampton Women's Survey. METHODS: In 493 mother-offspring pairs, we assessed linear size using high-resolution ultrasound at 11, 19, and 34 wk gestation (femur length) and at birth and 1, 2, 3, 4, and 6 y (crown-heel length/height). SD scores were created and conditional regression modeling generated mutually independent growth variables. Children underwent hip dual-energy X-ray absorptiometry (DXA) at 6 y; hip structure analysis software yielded measures of geometry and strength. RESULTS: There were strong associations between early linear growth and femoral neck section modulus (Z) at 6 y, with the strongest relationships observed for femur growth from 19 to 34 wk gestation (β = 0.26 cm(3)/SD, P < 0.0001), and for height growth from birth to 1 y (β = 0.25 cm(3)/SD, P < 0.0001) and 1 to 2 y (β = 0.33 cm(3)/SD, P < 0.0001), with progressively weaker relationships over years 3 (β = 0.23 cm(3)/SD, P = 0.0002) and 4 (β = 0.10 cm(3)/SD, P = 0.18). CONCLUSION: These results demonstrate that growth before age 3 y predicts proximal femoral geometry at 6 y old. These data suggest critical periods in which there is capacity for long-term influence on the later skeletal growth trajectory.