Women with severe diabetic angiopathy showed reduced placental blood flow, perhaps secondary to spiral artery vasculopathy, but women with gestational diabetes also showed reduced flow rates. Stasis would not seem to be a significant factor in spiral arteries given the high flow of utero-placental blood. Whether a thrombus forms in a blood vessel is a dynamic balance between the factors that lead to thrombus formation and those opposed, including those that lyse, that is digest, the thrombus. This is so not only because maternal blood carries necessary foodstuffs to the fetus and removes waste products throughout pregnancy but also because the quantity of oxygen delivered to the placenta is limited directly by the rate of PBF. Together, these programmed effects will potentially create an imbalance between insulin secretion and insulin-stimulated glucose utilization in the neonate, which probably explains the transient hyperinsulinism and hypoglycemia in some IUGR infants. Interestingly, the arteries appear to perfuse in separate intervals, and not all the arteries at once. Placental pathology demonstrated an immature placenta with evidence of acute chorioamnionitis and funisitis. Case reports can not show an epidemiologic correlation between a test and an outcome, but they can provide insight based on logical inferences of mechanism that can’t be obtained by epidemiological methods. Studies, for example from percutaneous sampling of umbilical cord blood, demonstrate that some growth retarded infants are hypoxic/acidotic(Nicolaides, Economides et al. The UV is a thin‐walled blood vessel, which has a sonographically measured average diameter of approximately 1.0–2.5 mm during 11–18 weeks 16 and 2.5–6.7 mm in the intra‐abdominal portion 17, 18 and 3.5–8.0 mm in the free loop of the umbilical cord 19 at 18–41 weeks of gestation. (2010). Villous venous constriction is a surprisingly plausible mechanism of stopping blood flow. 8). Naeye, R. L. (1992). (A) Membranes and (B) chorionic plate with marked infiltrate of neutrophils. “D” infarctions appear to be older true infarctions, while other designations are for different ages of intervillous thrombus. Original recordings of amniotic fluid pressure and fetal heart rate shown with proportionate systolic blood pressure changes and theoretical placental blood flow changes during antihypertensive therapy in two severely toxemic patients with intrauterine growth retardation. This is evidenced by persistence of the muscularized vascular walls in the decidua and can be diagnosed by placental bed biopsies or decidua, which remains on the placenta after deliver. 17. Acting by the two mechanisms discussed above, increasing Re and decreasing perfusion pressure, myometrial contractions decrease PBF in direct proportion to the intensity and duration of each contraction. 14D). He noted a correlation of increased percentage of infarction with low birth weight and that 7 of 8 placentas with more than 30% infarction were from stillbirths. Fetal blood within the villi is nearly all blast forms.