[Effect of ritodrine hydrochloride on uterine and umbilical blood flow in patients with preeclampsia and IUGR].
Ritodrine hydrochloride is clinically used to prevent uterine contraction in preterm labor. Pregnancy toxemia is known to be a cause of intrauterine growth retardation (IUGR) due to disturbance of utero-placental circulation. In the present study, patients with preterm labor or pregnancy toxemia associated with IUGR were infused with ritodrine and the effects of ritodrine on uterine and umbilical blood flow were determined by using 2-D color Doppler. The effects of ritodrine infusion on fetal growth were also evaluated. Increases in fetal heart rate and maternal heart rate were observed following ritodrine infusion, but there was no other apparent side effect. The resistance index (RI) of the uterine and umbilical arteries of patients with preterm labor were significantly decreased by ritodrine infusion. The RI of both arteries of the patients associated with toxemia and IUGR was also decreased. A significant increase in FTA and EFBW was observed in IUGR fetuses following treatment with ritodrine for 2 weeks given to patients with toxemia when compared with the non-treated control. These results indicate that ritodrine administration may be effective not only in preventing preterm labor but also in treating IUGR by improving utero-placental blood flow.
Kumazawa
T
T
Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo.
Suzuki
M
M
Saito
H
H
Yanaihara
T
T
D005260:Female; D005317:Fetal Growth Retardation / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007752:Obstetric Labor, Premature / Q000503:physiopathology / Q000517:prevention & control; D011225:Pre-Eclampsia / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D011247:Pregnancy; D012039:Regional Blood Flow / Q000187:drug effects; D012312:Ritodrine / Q000627:therapeutic use*; D015149:Tocolytic Agents / Q000627:therapeutic use*; D014470:Umbilical Cord / Q000098:blood supply*; D014599:Uterus / Q000098:blood supply*
D015149:Tocolytic Agents; D012312:Ritodrine