Influence of perinatal factors on the onset of puberty in boys and girls -Implications for interpretation of link with risk of long term diseases

The authors examined the hypothesis that perinatal factors influence the on set of puberty. Children born as singletons in Uppsala, Sweden, in 1973-197 7 were followed for height development before and during their school years (through 16 years of age). In all, 62 children born after preeclampsia, 12 9 born prematurely, 90 born small for gestational age, 175 born large for g estational age, 49 born short for gestational age, and 38 born tall for ges tational age were compared with 688 "normal" children. Differences in age a nd height at puberty onset and age at menarche were analyzed using the t te st and analyses of covariance. For boys, the mean age at puberty onset did not differ between normal boys and those with perinatal factors. Boys born small or short for gestational age were 4 cm shorter than normal boys, and those born large for gestational age were 3 cm taller than normal boys. Amo ng girls, patterns for differences in height were similar. Girls born small for gestational age were 5 months younger than normal girls at the onset o f puberty and menarche. Patterns of early childhood growth seemed to explai n the relations between these perinatal factors and height and age at puber ty. The authors conclude that body size at birth affects stature at puberty ; in girls, smallness for gestational age is associated with earlier pubert y. Associations between intrauterine exposures and disease risk may be conf ounded by, or mediated through, effects on adolescence.