A study of the differentials in fertility of Iraq's Mohafadhas, and the association of fertility with various socio-cultural factors, is handicapped for want of the reliable vital statistics from which measures of fertility can be satisfactorily derived. The alternative method, using a simple measure of fertility, the child–woman ratio, which requires only a knowledge of the population in age groups is therefore used. Since this measure is computed from census statistics, it is affected by differences in enumeration errors and in mortality and migration. An attempt has been made in this paper to keep these factors constant by using a modified child–woman ratio for comparing fertility levels.

The analysis showed that fertility rates vary from region to region, between Mohafadhas within a region and between rural and urban areas. One important broad geographic variation was that the Northern region was the area of high fertility. For the Mohafadhas, significant differences were noted in only six of the sixteen Mohafadhas of Iraq. Rural–urban difference was minimal, with few exceptions, and it was not always in the same direction. The intra-rural variations in the fertility ratio were far more important than intra-urban differences.

Correlation analysis showed that the average age at marriage, the proportion never married and the sex ratio in the reproductive ages were the important factors in explaining fertility differences between Mohafad has. There was virtually no correlation between fertility and urbanization or literacy.