ReviewMaternal exposure to di-2-ethylhexylphthalate and adverse delivery outcomes: A systematic review

•The evidence on association of DEHP with adverse pregnancy outcomes is inconsistent.•Heterogeneity of the included studies precludes a direct comparison of the findings.•Some of the findings should be interpreted with caution due to design limitations.•Future studies should address methodological concerns identified in this review.

Adverse pregnancy outcomes, including preterm delivery, short gestational age, and abnormal birth weight, remain a public health concern. The evidence on the association of the most common phthalate, di-2-ethylhexyl phthalate (DEHP) with adverse pregnancy outcomes remains equivocal. This systematic review summarizes published studies that investigated the association of DEHP with preterm delivery, gestational age, and birthweight. A comprehensive literature search found 15 relevant studies, most of which evaluated more than one outcome (four studies for preterm delivery, nine studies for gestational age, and ten studies for birthweight). Studies varied greatly with respect to study design, exposure assessment, analytical methods, and direction of the associations. We identified important methodological concerns which could have resulted in selection bias and exposure misclassification and contributed to null findings and biased associations. Given limitations of the previous studies discussed in this review, more thorough investigation of these associations is warranted to advance our scientific knowledge.