BIRTH-WEIGHT OF TWINS - 1 - THE FETAL GROWTH-PATTERNS OF TWINS AND SINGLETONS

Distributions of birth weights of twins and singletons born at three s outheastern Brazilian hospitals were compared after adjustment for ges tational age, its quadratic and cubic terms, sex, type of pregnancy, a s well as their interactions. The pattern of twin fetal growth rate wa s retarded in comparison to that of singletons, regardless of the soci oeconomic level of the examined population, but the gestational age at which this retardation started seems to be correlated to the income o f the mothers. In all cases, after 28 weeks of gestation, female fetal growth was slightly but consistently lower than that of males.