“…Third, we included only studies published in English, and there may well be studies published in other languages that could shed further light on placental biomarkers. Fourth, there are many causes of SGA, including maternal, fetal, and placental factors (Zabransky, 2013); thus, studies that examine only placental biomarkers, excluding maternal and fetal factors, may be too limited in identifying reliable predictors of SGA infants. Finally, the adverse pregnancy outcomes of some studies included in this review were not independent of one another.…”