The Effect of Tocolysis by Oral Nefidipine on Doppler Velocimetry of Umbilical, Middle Cerebral Arteries and Ductus Venosus

Abstract
Aim of Work: To assess effect of nifedipine administration as a tocolytic agent on placental and fetal cerebral blood flow as well as on fetal cardiac function by measuring Pulsatility Index (PI) of the umbilical artery, Middle Cerebral Arteries (MCA) and Ductus Venosus (DV) twice, immediately before initial nifedipine dose and 24 hours after the therapy.
Methods: Prospective, observational, analytic cohort, clinical trial involved 70 women with single viable fetus between 24-35 weeks undergoing tocolysis by nifedipine. Pulsatility Index (PI) of the umbilical artery, Middle Cerebral Arteries (MCA) and Ductus Venosus (DV) was assessed twice, immediately before initial nifedipine dose and 24 hours after the therapy.
Results: The mean age of pregnant participants was (28.6±  3.1), mean Body Mass Index (BMI) was (22.2±1.3). There was no significant effect of nifedipine on Hemodynamic parameters (maternal heart rate, systolic blood pressure and diastolic blood pressure). There was no statistically significant difference of Pulsatility Index (PI) of the umbilical artery, Middle Cerebral Arteries (MCA) and Ductus Venosus (DV) before and after treatment.
Conclusion: Oral nifedipine is a safe tocolytic agent on placental and fetal cerebral blood flow as well as on fetal cardiac function when used in pregnant women at risk of preterm delivery during the first 24 hours.