Shared and disparate components of the pathophysiologies of fetal growth restriction and preeclampsia

Intrauterine growth restriction (IUGR) and preeclampsia differ in their association with maternal disease but share a similar placental pathology. Moreover, mothers who have had pregnancies complicated by preeclampsia or IUGR are at elevated later-life cardiovascular risk. Why, then, do some women develop IUGR and others develop preeclampsia? In this clinical opinion, based on a review of the literature, we hypothesize that both women experiencing preeclampsia and IUGR enter pregnancy with some degree of endothelial dysfunction, a lesion that predisposes to shallow placentation. In our opinion, preeclampsia develops when abnormal placentation, through the mediator of elevated circulating cytokines, interacts with maternal metabolic syndrome, comprised of adiposity, insulin resistance/hyperglycemia, hyperlipidemia, and coagulopathy. IUGR develops in the absence of antenatal metabolic syndrome. Among these women, the baby is affected by shallow placentation but the mother does not develop clinically apparent disease. This conceptualization provides a testable framework for future etiologic studies of preeclampsia and IUGR.