Contrast-enhanced ultrasonography of uteroplacental circulation does not evoke harmful CTG changes or perinatal...

To determine whether an intravascular ultrasound contrast agent used in the examination of uteroplacental circulation in late pregnancy has any effect on fetal cardiotocographic (CTG) parameters or fetal well-being.

The uteroplacental circulation of 69 women with singleton third trimester pregnancies was examined by power Doppler with contrast agent (Levovist((R)); Schering AG, Berlin, Germany) enhancement. Computed CTG examination using Dawes/Redman criteria was recorded just before and after ultrasonographic examination in 25 subjects examined with contrast agent and in 15 control patients who were given only physiological saline injection during ultrasonography. Umbilical artery blood flow velocity waveform was examined in 15 subjects before and 5 min after maternal contrast agent injection. Obstetric outcome of all the 69 subjects was evaluated by birthweight, placental weight, fetal and neonatal distress, prenatal hemorrhages, cord arterial and venous blood pH and macroscopic placental examination.

No apparent fetal or maternal harmful effects caused by the contrast-enhanced ultrasonography were observed. In CTG examination there was a statistically significant increase in the number of accelerations and fetal movements and in short-term variation after administration of the contrast agent in both subjects and controls. There were no significant changes in the umbilical artery blood flow velocity waveform after administration of the contrast agent.

Contrast agent enhancement in the examination of uteroplacental circulation does not produce any harmful fetal or placental effects in late pregnancy. Ultrasonographic examination itself, obviously due to maternal stress reaction, is associated with a slight activation of fetal behavioral status.