Doppler velocimetry of the uterine and fetal circulations during prostaglandin E2 cervical ripening.

Abstract

The objective of the study was to investigate flow characteristics of the maternal uterine and fetal umbilical and middle cerebral arteries following intracervical administration of prostaglandin E2 (PGE2). Doppler velocimetry of uterine, umbilical and middle cerebral arteries was performed immediately before and 2 h after PGE2 administration in 28 women with uncomplicated post-term pregnancy and an unfavorable cervix. Placental position was determined in all cases. When all patients were considered jointly, regardless of placental position, the mean uterine artery resistance index (RI) values were 0.41 +/- 0.07 before and 0.48 +/- 0.13 2 h after PGE2 administration (p < 0.05). When patients with lateral placentas (n = 20) were analyzed separately, only the non-placental uterine artery showed a significant increase 2 h after PGE2 administration, whereas no significant differences were found in the placental uterine artery. No changes were observed in uterine RI values of patients with central placentas. No significant differences were observed for umbilical artery and middle cerebral artery before and after PGE2 administration. It is concluded that intracervical PGE2 administration increases uteroplacental resistance but probably does not substantially affect placental perfusion; that the umbilical circulation is not affected; and that there were no signs of redistribution of fetal blood flow.