A comparison of the effects of the most commonly used tocolytic agents on maternal and fetal blood flow

Mahmut Güden,Iltaç Akkurt,Necmi Ömer Kandemir,And Yavuz,Serenat Eriş Yalçın,Bora Coşkun,Mehmet Özgür Akkurt,Bülent Yirci

doi:10.4274/tjod.25993

Abstract

Objective:To investigate the effects of two tocolytics, nifedipine and magnesium sulfate, on Doppler indices in maternal and fetal vessels.Materials and Methods:We recruited 100 pregnant women with preterm birth between 24-36 gestational weeks who were admitted to our tertiary center over a two-year period. Patients were allocated to nifedipine (n=49) and magnesium sulfate (n=51) groups and Doppler indices of umbilical, middle cerebral, uterine arteries, and ductus venosus were measured before and after tocolysis.Results:There were no differences between the groups in terms of maternal age, gestational week, body mass indexes, cervical dilation, effacement at admission, birth weights and latency periods until birth. Nifedipine decreased resistance indexes in uterine arteries but magnesium sulfate increased resistance especially in the right uterine artery. Nifedipine significantly decreased systole to diastole and resistance index in the umbilical artery, magnesium sulfate increased systole to diastole and resistance index but this was not statistically significant. Nifedipine acted variably on resistance index and pulsatility index in the ductus venosus; however, magnesium sulfate increased resistance. Nifedipine decreased pulsatility index in the middle cerebral artery, contrary to magnesium sulfate with which it increased.Conclusion:Nifedipine had favorable effects on maternal and fetal vessel indexes but magnesium sulfate increased resistance. Despite the proposed neuroprotective benefits of magnesium sulfate, nifedipine seems to be a better and safer tocolytic agent than magnesium sulfate due to its positive beneficial effects on maternal and fetal vessels.

Highlights

Despite the developments in medicine and technology, preterm birth (PTB) is still the leading cause of perinatal morbidity and mortality
The rate of other obstetric complications has declined with the development of contemporary obstetric understanding, the treatment methods developed for preterm labor (PTL) have so far failed to reduce the number of PTBs
No statistically significant difference was observed in umbilical artery PI, resistance index (RI) and systole to diastole (S/D) rates (p=0.358, p=0.556, and p=0.534, respectively)

Summary

Introduction

Despite the developments in medicine and technology, preterm birth (PTB) is still the leading cause of perinatal morbidity and mortality. Early-term complications such as respiratory distress syndrome, necrotizing enterocolitis, and intraventricular hemorrhage are frequent problems in preterm infants[1,2]. The rate of other obstetric complications has declined with the development of contemporary obstetric understanding, the treatment methods developed for preterm labor (PTL) have so far failed to reduce the number of PTBs. some benefits are gained through prolongation of pregnancy to enable corticosteroid administration to accelerate fetal lung maturation. In addition to their success in stopping the premature uterine contractions, presents maternal and fetal adverse effects. The use of these drugs requires close monitoring of patients during their administration[4]. The aim of this study was to determine and compare the effects of nifedipine and magnesium sulfate (MgSO4), the most commonly used tocolytic agents, on maternal and fetal blood flows

Methods

Results

Discussion

Conclusion