Arezoo Bagheri - Assistant professor, National Population Studies, Comprehensive Management Institute, Tehran, Iran
Mahsa Saadati - Assistant professor, National Population Studies, Comprehensive Management Institute, Tehran, Iran

Background & aim: Demands for more children have substantial effects on couple’s fertility behaviors. The ideal number of children for most Iranian’s family is two, so that it is reasonable to study which factors determine women’s decision to have a third child. The main aim of this study was to examine factors affecting the demand for a third child (DTC). Methods: This cross-sectional study was conducted on 6231 Iranian married women from all provinces during autumn 2014. Participants in the study were selected by multistage stratified sampling method. A structured questionnaire was employed to collect the related data. Finally, the analysis included 2272 DTC questionnaires for women with two children by applying a classification tree model. Results: In this study,50.7% of women with two children had no desire for having the third child, out of whom 71.1% (79) were living in the provinces with total fertility rate (TFR) less than 2 and in urban areas, respectively. Most of them with the educational level of diploma or lower (78.2%) had a negative opinion about having the third child (36.1%). Based on the classification and regression tree algorithm, women who were interested in having their third child in provinces with TFR more than 2 included rural women, urban women with positive opinion toward childbearing, and those with educational level of secondary school. However, women who were keen on having their third child in provinces with TFR less than 2 consisted of urban women aged 30-49 with educational level of high school or lower, those younger than 30 years with positive opinion who married in their 20-29, rural women aged less than 30, and rural women aged 30-49 with positive opinion who married in their 20-39. Conclusion: Women’s place of residence and opinion toward childbearing had important effects on their DTC. However, women’s educational level as well as their age and marriage age could affect their DTC in provinces with TFR less than 2 compared to other provinces.

Fertility Behavior, Fertility Determinants, Child, Women, Decision Trees