Causes of most birth defects are largely unknown. Genetics, maternal factors (e.g., age, smoking) and environmental exposures have all been linked to some birth defects, including neural tube, oral cleft, limb reduction, and gastroschisis; however, the contribution of cumulative exposures across several environmental domains in association with these defects is not well understood.

中文翻译：

---

德克萨斯州累积环境质量与十种选定出生缺陷之间的关联。

大多数出生缺陷的原因在很大程度上是未知的。遗传、母体因素（如年龄、吸烟）和环境暴露都与一些出生缺陷有关，包括神经管、口裂、肢体减少和腹裂；然而，与这些缺陷相关的几个环境领域的累积暴露的贡献尚不清楚。