[Comparison of Doppler ultrasound assessment of utero-placento-fetal perfusion in normal pregnancies and in those with threatened premature labor].

The aim this study to compare perfusion parameters, measured by Doppler sonography, between normal pregnancies and pregnancies with symptoms of preterm labor. The patient collective comprised of 3 groups: 62 normal pregnancies (group 1), 23 preterm labor before tocolysis (group 2) and 114 preterm labor up to 48 hours under tocolysis (group 3). In each case pulsatility index was measured in the uterine artery on the placental side and non-placental side, umbilical artery, fetal descending aorta and middle cerebral artery. In the contrary to patients in group 1, patients in group 2 and 3 showed significantly elevated PI values in uterine artery placental side and non-placental side, respectively. The median of PI for both uterine arteries in both groups was significantly higher compared to that of group 1. However, 1/3 of patients with preterm labor showed pathologic uterine perfusion before or during tocolysis. The values of PI in umbilical artery, fetal descending aorta and middle cerebral artery did not reveal significant difference in all group. Nevertheless, 30% of pregnancies with preterm labor have pathological perfusion in the fetal descending aorta. We conclude that some patients with symptoms of preterm labor have pathological perfusion in uterine arteries and fetal descending aorta not induced by uterine contractions. We believe that the complex assessment of uterine perfusion should include the median PI value of both uterine arteries in order to have a reliable information. A short-term intravenous tocolysis with betamimetics does not seem to have a positive influence on the hemodynamic insufficiency.