Background and Objectives: The study aimed to evaluate the effect of the oral administration of drotaverine on maternal and fetal circulation as measured by Doppler sonography in women with a risk of preterm birth. Materials and Methods: The present prospective study was conducted on 34 women with singleton pregnancy at 26–36 weeks of gestation. Doppler flow and pulsatility index (PI) assessments of the umbilical artery, fetal middle cerebral artery, and uterine arteries were performed before and 90–120 min after oral drotaverine administration. Results: There were no statistically significant differences between the Doppler assessment (PI Uma—umbilical artery, MCA—middle cerebral artery, and ltUta—left uterine artery) before drotaverine administration and 90–120 min after oral intake, but there were statistically significant differences between the PI assessment of the rtUta (right uterine artery, 0.55 vs. 0.75, p = 0.05) and the mean of the Uta (0.66 vs. 0.74, p = 0.03). For changes in the CUR (cerebro–umbilical ratio) and % changes in the CUR and mean PI of the Uta, there was no correlation with obstetric history, AFI (amniotic fluid index), gestation week, infertility history, systolic pressure, or diastolic pressure. There was a statistically positive correlation between changes in the CUR and % change in the CUR and body weight and in height. Conclusions: Drotaverine has no statistically significant influence on the MCA and Uma PI. The oral administration of drotaverine has an impact on PI rtUta and the mean PI Uta.