Adaptive changes in the splenic artery and left portal vein in fetal growth restriction.

ABSTRACT

OBJECTIVES: The purpose of this study was to determine whether a low splenic artery pulsatility index (PI) and reduced flow through the left portal vein are involved in redistribution of fetal growth restriction. METHODS: Forty-two women with prenatally diagnosed intrauterine growth restriction of singleton fetuses were included. The next pregnant woman with an appropriately growing fetus, matched for gestational age, was selected as a control. Blood flow velocities were measured in the splenic artery and left portal vein. Obstetric and perinatal information was obtained from standardized medical records. RESULTS: The blood flow through the left portal vein was significantly reduced compared with the controls (P < .0001). Placental impairment in fetal growth restriction was clearly linked to a decreased splenic artery PI (P = .0004). In growth-restricted fetuses with reduced left portal vein flow and a splenic artery PI below the 5th percentile, perinatal mortality, a low 5-minute Apgar score, and neonatal metabolic acidosis were observed significantly more often (P = .04, .01, and .004; P = .03, .03, and .006, respectively). CONCLUSIONS: Reduced blood flow through the left portal vein and low resistance in the splenic artery can be found in growth-restricted fetuses with adverse neonatal outcomes.