Zare Najaf, Nouri Bijan, Moradi Fariba, Parvareh Maryam
Department of Biostatistics, Infertility Research Center , Shiraz University of Medical Sciences, Shiraz, Iran.
Social Determinants of Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran.
Int J Reprod Biomed. 2017 Jan;15(1):11-16.
Time to first pregnancy (TTFP) has never been studied in an Iranian setting. Lifestyle, occupational and environmental factors have been suggested to affect the female reproduction.
This study was conducted to measure TTFP in the south of Iran and survey the effects of several similar factors on TTFP by frailty models.
The data on TTFP were available for 882 women who were randomly selected from the rural population (the south of Iran). Only the first and the planned pregnancies of every woman were included. The data were collected retrospectively by using self-administered questionnaires. Frailty and shared frailty models were used to determine which factors had the highest impact on TTFP.
The median TTFP was 6.4 months and several factors were surveyed. However, only the age of marriage, height, maternal education and regularity of menstruation prior to conception were selected in the multivariable models.
Among the several factors which were included in the study, the result of frailty model showed that the height, age of marriage and regular menstruation seemed more notable predictors of TTFP.
首次怀孕时间（TTFP）在伊朗的情况从未被研究过。有研究表明生活方式、职业和环境因素会影响女性生殖。
本研究旨在测量伊朗南部的首次怀孕时间，并通过脆弱模型调查若干类似因素对首次怀孕时间的影响。
从农村人口（伊朗南部）中随机选取882名女性，获取她们首次怀孕时间的数据。仅纳入每位女性的首次且计划内怀孕情况。通过自填问卷回顾性收集数据。使用脆弱模型和共享脆弱模型来确定哪些因素对首次怀孕时间影响最大。
首次怀孕时间的中位数为6.4个月，并对若干因素进行了调查。然而，多变量模型中仅选择了结婚年龄、身高、母亲教育程度和受孕前月经周期规律情况。
在本研究纳入的若干因素中，脆弱模型结果显示身高、结婚年龄和月经规律似乎是首次怀孕时间更显著的预测因素。
