Impact of age at first birth and birth interval on fertility: a case study of Temeke District.

This study attempts to investigate the impact of age at first birth and birth interval on fertility. The influence of demographic and socio-economic variables on the above variables and linkage between them as well as with children ever born are quantified. The variables covered in the study are children ever born, age at first birth, mean birth interval, breast feeding, contraceptive use, contraceptive knowledge, present age and its second and third power, educational level, marital status, marriage type, residence, occupation and religion. Descriptive analysis is utilised to identify the characteristics of the study population and multiple regression analysis is used to identify the significant variables which influence fertility. Moreover correlation and path analyses are utilised to explain the directional flow and quantify the linkage between variables and age at first birth and birth interval in influencing fertility. The outcome of the study shows that age at first birth and birth interval are powerful determinants of fertility rate. When the two variables are combined they raise the rate of fertility decline. Among the demographic and socio-economic variables education at secondary level has been observed to be a strong limiting fertility factor since it raises the age at first birth to 20 years and above. Also it has been observed to influence other variables directly in affecting fertility. The mean age at first birth has been observed to be 19.2 years. The mean birth interval of 2.75 years and above has been observed to affect fertility. This is influenced by fecundity and breast feeding. Contraceptive use has been observed to increase the birth interval to above 3.25 years. The mean birth interval has been observed to be 3.6 years. The increase in contraceptive use is directly proportional to a rise in educational level. Religion has an indirect influence on fertility because of its influence on education and age at first birth.