PREDICTION OF MORBIDITY IN SMALL AND NORMALLY GROWN FETUSES BY FETAL HEART-RATE-VARIABILITY, BIOPHYSICAL PROFILE SCORE AND UMBILICAL ARTERYDOPPLER STUDIES

Objective To assess the ability of noninvasive tests of fetal wellbein g to predict hypoxic morbidity independent of fetal size. Design A pro spectively planned, longitudinal, observational study. Setting Fetal S urveillance Unit, King's College Hospital, London. Subjects One hundre d and ninety-one pregnant women with singleton pregnancies who were de livered after 32 weeks' gestation who were seen in the Fetal Surveilla nce Unit within seven days of delivery. Interventions Fetal surveillan ce by fetal abdominal circumference, heart rate variability (mean rang e), biophysical profile score and umbilical artery pulsatility index m easurements. Main outcome measures Birthweight was classified as > or less-than-or-equal-to 2.5th centile (AGA or SGA) for gestational age a nd sex. Morbidity was defined as at least one of the following at birt h: delivery by emergency caesarean section for fetal distress, umbilic al venous blood pH less than 7.15, 5 min Apgar score less than 7 or ad mission to the Special Care Baby Unit (SCBU). Results Fetal abdominal circumference was the best indicator of which fetuses (n = 30) would b e SGA. Fourteen of the 30 (47%) SGA fetuses had morbidity at birth and abnormal umbilical Doppler studies' significantly predicted this (chi 2 = 2.93, P = 0.003). By contrast, fetal heart rate variability and th e biophysical profile score did not. Twenty-seven of the 161 (17%) AGA fetuses had morbidity at birth, but this was not significantly predic ted by heart rate variability, biophysical profile score or umbilical Doppler studies. Conclusions None of the antenatal testing techniques studied predicted morbidity in normally grown fetuses but Doppler stud ies indicated whether a small fetus was 'sick small' or 'normal small' .