Impact of Doppler sonography on intrauterine management and neonatal outcome in preterm fetuses with intrauterine growth restriction

Abstract

To test the hypothesis that earlier delivery may be warranted to improve neonatal outcome of fetuses with intrauterine growth restriction (IUGR) with abnormal Doppler parameters. This was a retrospective cohort study of 110 fetuses with an antenatal diagnosis of IUGR due to placental insufficiency which had a very low birth weight (< 1500 g), delivered at the Department of Fetomaternal Medicine of the Medical University of Vienna, Austria, between January 1999 and July 2009. Doppler results before delivery were classified as follows: Group 1: abnormal umbilical artery (UA) pulsatility index (PI) more than 2 SD above the mean for normal reference data, or absent UA end-diastolic flow, both with normal middle cerebral artery (MCA) PI (mean ± 2 SD); Group 2: abnormal UA-PI > mean + 2 SD, or absent or reversed UA end-diastolic flow, with abnormal MCA-PI (< mean - 2 SD) and normal ductus venosus (DV) PI (mean ± 2 SD); Group 3: absent or reversed UA end-diastolic flow, with abnormal MCA-PI (< mean - 2 SD) and abnormal DV-PI (> mean + 2 SD) and/or absent or reversed end-diastolic DV flow. Pregnancy outcome was analyzed according to Doppler results. Due to very poor prognosis, 19 fetuses underwent expectant management and died in utero. These were excluded from further analyses. Of the remaining 91 cases, 17 were in Doppler Group 1, 44 in Group 2 and 30 in Group 3. Within 4 weeks after delivery, 0/17 (0%) infants in Group 1 died, 2/44 (4.5%) infants in Group 2 died and 7/30 (23.3%) infants in Group 3 died (P = 0.019). None of the 42 Group 2 cases that delivered at or after 28 completed gestational weeks died within 4 weeks after delivery, in contrast to 4/20 (20.0%) Group 3 cases (P = 0.009). In comparison, among infants delivered before 27 completed gestational weeks, 2/2 (100%) Group 2 cases died and 3/10 (30.0%) Group 3 cases died; P = 0.152). Doppler examinations are highly predictive in assessing the outcome of IUGR fetuses. From 28 completed gestational weeks, early delivery before the onset of fetal cardiac decompensation might be beneficial.