A LONGITUDINAL-STUDY OF GROWTH AND DEVELOPMENT OF STATURE AMONG PRENATALLY EXPOSED ATOMIC-BOMB SURVIVORS

Growth retardation due to exposure to the atomic bomb has been evaluated using repeated measurements of stature from 10 to 18 years of age. A highly significant growth retardation due to the DS86 uterine dose was observed in all trimesters combined and in the first and second trimesters of pregnancy. In the first trimester, all parameter estimates based on a linear (L) or linear-quadratic (L-Q) dose-response relationship were negative in relation to the DS86 uterine dose. The positive dose estimate in the second trimester is small and close to the control level. Statistically significant difference was determined by a multivariate test statistic examining whether or not a set of two- or three-parameter estimates including a constant term related to an L or L-Q dose-response relationship was different from zero. A radiation- related growth retardation was demonstrable as a longitudinal result of the repeated measurements of stature. The dose effect in the third trimester was not significant under either the L or the L-Q model. The relationship between birth weights and repeated measurements of stature in adolescence is discussed based on the results obtained by a growth curve analysis.