Purpose

To advance knowledge about childhood neurodevelopmental disorders and study their environmental determinants, we conducted a study in Tehran, Iran to assess the feasibility of prospective birth cohort study.

Methods

We evaluated participation of pregnant women, feasibility of sampling biological material, and health care services availability in Tehran in four steps: (1) first trimester of pregnancy; (2) third trimester of pregnancy; (3) at delivery; and (4) two to three months after delivery. We collected related data through questionnaires, also various biological samples were obtained from mothers (blood, urine, milk and nails—hands and feet) and newborns (umbilical cord blood, meconium, and urine samples) from February 2016 to October 2017.

Results

overall 838 eligible pregnant women were approached. The participation rate was 206(25%) in our study and about 185(90%) of subjects were recruited in hospitals. Out of 206 participants in the first trimester, blood, urine, hand nail, and foot nail samples were collected from 206(100%),193(93%), 205(99%), and 205(99%), respectively. These values dropped to 65(54%), 83(69%), 84(70%), and 84(70%) for the remaining participants 120(58%) in the third trimester, respectively. Also, we gathered milk samples from 125(60%) of mothers at two to three months after delivery.

Conclusion

Our findings suggest that hospitals were better places for recruitment of subjects in a birth cohort in Tehran. We further concluded that birth cohort study recruitment can be improved by choosing appropriate gestational ages. Obtaining the newborn’s urine, meconium, and umbilical cord blood were challenging procedures and require good collaboration between hospital staff and researchers.

中文翻译：

---

德黑兰环境和神经发育障碍 (TEND) 队列研究：第一阶段，可行性评估

目的

为了提高有关儿童神经发育障碍的知识并研究其环境决定因素，我们在伊朗德黑兰进行了一项研究，以评估前瞻性出生队列研究的可行性。

方法

我们分四个步骤评估了德黑兰的孕妇参与、生物材料取样的可行性和医疗保健服务的可用性：（1）怀孕的前三个月；(2)妊娠晚期；(3) 交货时；(4) 产后二至三个月。我们通过问卷调查收集了相关数据，并从2016年2月至2017年10月期间从母亲（血液、尿液、牛奶和指甲——手和脚）和新生儿（脐带血、胎粪和尿液样本）中获取了各种生物样本。

结果

总共接触了 838 名符合条件的孕妇。在我们的研究中，参与率为 206（25%），大约 185（90%）的受试者在医院招募。在妊娠早期的 206 名参与者中，分别从 206（100%）、193（93%）、205（99%）和 205（99%）中收集了血液、尿液、手指甲和脚指甲样本。在妊娠晚期，其余参与者 120（58%）的这些值分别下降到 65（54%）、83（69%）、84（70%）和 84（70%）。此外，我们还收集了 125 名（60%）母亲在分娩后 2 到 3 个月时的牛奶样本。

结论

我们的研究结果表明，医院是德黑兰出生队列中招募受试者的更好场所。我们进一步得出结论，可以通过选择适当的胎龄来改善出生队列研究的招募。获取新生儿的尿液、胎粪和脐带血是具有挑战性的过程，需要医院工作人员和研究人员之间的良好合作。