Liver Function Tests and Glucose and Lipid Metabolism in Growth-Restricted Fetuses ALISTAIR ROBERTS, MD, SIMONA NAVA, MD, LUISA BOCCONI, MD, SARAH SALMONA, MD, AND UMBERTO NICOLINI, MD Objective: To assess hematologic and biochemical blood variables in growth-restricted fetuses and relate them to biophysical measurements. Methods: Blood was sampled from 22 growth-restricted fetuses. All had normal karyotypes and no congenital infec- tions. Venous pH, partial pressure of oxygen, hematocrit, glucose, uric acid, urea, creatinine, total protein, total and direct bilirubin, aspartate aminotransferase, alanine amino- transferase, -glutamyltransferase, alkaline phosphatase, lactic dehydrogenase, amylase, pseudocholinesterase, creat- inine kinase, triglycerides, and cholesterol were measured and compared with our reference range. Results: Ultrasound measurements of abdominal circum- ference correlated with fetal pH (r 0.64), partial pressure of oxygen (r 0.52), glucose (r 0.67), total bilirubin (r 0.54), lactic dehydrogenase (r 0.48), and triglyceride levels (r 0.65). Compared with fetuses with present end-diastolic velocities in the umbilical artery, the eight with absent end-diastolic velocities had lower pH (median z score 4.31), partial pressure of oxygen (median z score 2.39), glucose (median z score 2.01), and cholesterol (median z score 2.34), and higher -glutamyltransferase (median z score 2.43), lactic dehydrogenase (median z score 3.75), urea (median z score 1.33), creatinine (median z score 1.23), and triglyceride levels (median z score 1.71). Only triglycerides correlated with abdominal circumference, independent of Doppler results. Conclusion: Growth-restricted fetuses with absent end- diastolic velocities in the umbilical artery had more marked acidemia, hypoxemia, hypoglycemia, and abnormal liver function than those with end-diastolic velocities. Triglycer- ide levels were inversely related to fetal size independent of Doppler results. High triglyceride levels might reset fetal homeostatic mechanisms, leading to disturbances of lipid metabolism in later life. (Obstet Gynecol 1999;94:290 – 4. © 1999 by The American College of Obstetricians and Gynecologists.) Assessment of chromosome status and fetal acid-base balance was considered by some authors an important adjunct in the evaluation of certain pregnancies compli- cated by fetal growth restriction (FGR). 1 Fetal partial pressure of oxygen and pH at blood sampling were poorly associated with perinatal outcome, 2 but it was suggested that long-term neurologic impairment might be predicted by intrauterine fetal acidemia. 3 It is un- known whether fetal blood variables other than acid- base balance are related to outcome, and there is little information about liver function in growth-restricted fetuses, despite the decrease in liver size 4 and changes in liver blood supply 5 that accompany the condition. Changes in fetal acid-base balance can be predicted by changes in fetal Doppler evaluation of umbilical cord flow. 2,6–8 Whether that is true of other metabolic changes in the fetus needs to be investigated. There was a surge of interest in the association between fetal size at birth and adult diseases, including hypertension, diabetes, hypercholesteremia, and heart disease. 9 –11 Changes in fetal metabolic homeostasis from FGR might provide clues about such associations. The aim of this study was to investigate acid-base balance, hematologic, and biochemical variables in growth-restricted fetuses and relate them to fetal mea- surements, Doppler evaluation of cord flow, and amni- otic fluid volumes, well-recognized perinatal risk fac- tors. Materials and Methods Twenty-two consecutive growth-restricted fetuses had blood sampling during 1991–1995. The mothers were normotensive and free of diseases associated with FGR. Median gestational age was 24 weeks (range 21–38 weeks). Fetal blood sampling was done to investigate chromosome status and seek evidence of intrauterine infection. Each fetus had normal karyotype, no evi- dence of infection on the basis of standard immunologic From the 1st Department of Obstetrics and Gynecology, University of Milano, Clinica Mangiagalli, Milano, Italy. 290 0029-7844/99/$20.00 Obstetrics & Gynecology PII S0029-7844(99)00235-5