The relative aetiological importance of birth order and maternal age in mongolism

Open Access
Publisher Website
Google Scholar
Abstract
Data from the family histories of 224 mongolian imbeciles are presented. Statistical analysis, by 2 methods, shows that the numbers of imbeciles in each birth rank are very close to those which are to be expected on the assumption that the incidence of mongolism depends upon maternal age and not on birth order. This conclusion applies also to the number of first-born children found to be affected. Etiological significance can therefore not be attributed to birth order with any reasonable degree of probability. Neither is there any evidence that the long interval which sometimes precedes the birth of an affected child is of causal significance.

This publication has 4 references indexed in Scilit: