This book presents the theory that positional obstruction of the inferior vena cava by the gravid uterus might contribute to the causation of preeclampsia, fetal growth restriction, preterm birth, dysfunctional labor and uterine atony. Investigating this possibility is timely, since non-invasive technology now exists which detects hemodynamically significant obstruction of the inferior vena cava in real time, by relying on the fact that such obstruction causes an immediate decrease in maternal cardiac output. If further research shows that obstruction of uterine venous return at the inferior vena cava can cause maternal or fetal injury, systematic reduction of this obstruction during gestation might improve maternal and fetal outcomes. Written in a direct, informal and engaging style-- and enriched with clinical insights and abundant colorful graphics-- this thought-provoking and potentially ground-breaking work should be of interest to maternal and neonatal health professionals, including obstetricians, maternal-fetal medicine specialists, neonatologists, obstetric anesthesiologists and midwives.