Prenatal and postnatal growth and allometry of stature, head circumference, and brain weight in québec children

A recently proposed four-parameter generalization of the Gompertz curve (Jolicoeur et al., 1992a) is used to analyze chronological growth and allometry in the stature, head circumference, and brain weight of 101 male and 95 female fetuses and children autopsied at the Sainte-Justine Hospital for children in Montreal. Although asymptotic stature cannot be determined accurately because the sample does not include adults, the data nevertheless suggest that head circumference and brain weight terminate most of their growth much earlier than stature. This conclusion is also supported by the fact that, whereas the log-log relationship between head circumference and brain weight is almost straight and closely approximates simple allometry, the log-log relationships between stature, on one hand, and head circumference or brain weight, on the other hand, are markedly curved, indicating complex allometry. Applied to 78 males and 73 females whose total age is between 20 weeks and 1.5 years, the confidence intervals of the slope of the major axis of logarithmically transformed data indicate that the allometry exponent of brain weight relative to head circumference is somewhat higher than 3.0, which may reflect changes in head proportions. © 1993 Wiley-Liss, Inc.