بررسی عوامل مؤثر بر فاصله ازدواج تا تولد اول، با استفاده از مدل شفا‌یافته گمپرتز تعمیم‌یافته در استان آذربایجان غربی

Background & Objectives: Although several studies have been carried out for evaluation of the first birth interval, none of them has considered the presence of infertile women within the sample. Therefore, the aim of this study was to employ survival analysis to study the first birth interval and its determinant factors more accurately. Methods: In Data from 1068 married women of reproductive age in west Azarbaijan province were considered in this investigation. Two-stage sampling design was used to collect data via a questionnaire, modified Gompertz model, a special kind of cure models, was employed in this study. For descriptive and analytical data analysis, SPSS 16 and R 2.12 were used respectively. Results: In this study, the average interval between marriage and first birth was 3.9± 0.7 (± SD) years. Using modified Gompertz model, among all demographic factors only mother’s education had significant effect on the first birth interval so that with increasing mother’s educational level, the first birth interval had also increased. (P =0.007). In addition, the estimation of the proportion of women who did not have any children was 0.062 that showed a positive trend with increasing mother’s educational level. Conclusion: This study revealed that due to the presence of infertility among married women the use of Modified Cured Gompertz model is an appropriate method for evaluation of the first birth intervals and it's determinant factors.