Maternal Age at the Conception of the Congenitally Malformed Child

Abstract

In a preceding report1 it was shown that the first four children in a family are less likely to exhibit congenital deformities than are subsequent offspring.Since, of necessity, parents are older when their later children are born, this observation raised the question as to the age of the mother when defective children begin to be born more often than is expected by chance. The present report deals with this question. MATERIALS AND METHODSFive hundred and seventy families form the basis for the report. Each family possessed at least one congenitally malformed child who had died and for whom a death certificate had been filed. The home of each family was visited, and information was secured from the mother or a member of her immediate family concerning the year of her birth and that of each of her children.Information regarding the ages of the mothers at the births of 607 congenitally malformed children and 1,583 normally developed siblings was secured. The group of children included : (a) those for whom death certificates were available and (b) any other defective offspring of the mothers. The latter group of defective offspring included a few living malformed children as well as those who had died for whom no certificates were located. RESULTSThe data are considered under the following headings :1. Maternal age at birth of first normal and at birth of first defec¬ tive child.2. Early versus late marriage and interval before birth of first nor¬ mal and before birth of first defective child.3. Ratio of defective to normal offspring at various maternal ages.