Obstetric outcome after early placental complications

Purpose of review To evaluate the impact of early pregnancy complications involving placentation and early placental development on adverse obstetric outcome in ongoing and subsequent pregnancies. Recent findings We found an increased risk of adverse outcome (odds ratio > 2.0) in ongoing pregnancies of preterm delivery (PTD), very preterm delivery (VPTD), placental abruption, small for gestational age (SGA), low birth weight (LBW) and very LBW (VLBW) after a threatened miscarriage episode; pregnancy-induced hypertension, preeclampsia, placental abruption, PTD, SGA and low 5-min Apgar score following the detection of an intrauterine haematoma; and VPTD, VLBW and perinatal death after a vanishing twin phenomenon. In subsequent pregnancies, the risk of perinatal death was increased (odds ratio > 2.0) after a single miscarriage, the risk of VPTD after two or more miscarriages, the risk of placenta previa, premature preterm rupture of membranes, PTD, VPTD and LBW after recurrent miscarriage and the risk of VPTD after two or more terminations of pregnancy. Summary Our analysis of the literature review indicates a link between early pregnancy complications involving the placenta and subsequent adverse obstetric and perinatal outcomes. Some of these associations are based on limited or small uncontrolled studies. Larger population-based prospective controlled studies have recently been published confirming most of these findings. This suggests that the early detection of these risk factors could improve the screening of women at high risk of specific obstetric complications in ongoing and subsequent pregnancies.