The Impact of Nifedipine on Maternal and Fetal Blood Streamon The Threat of Preterm Labor

Abstract

Anita Deborah Anwar, Indra Magda Tiara, Elsy Nur Anggraeni, Rizna Tyrani Rumanti, Kemala Isnainiasih Mantilidewi, Jusuf S Effendy, Prima Nanda Fauziah

Preterm birth is a significant cause of perinatal morbidity and mortality and that becomes a major challenge in perinatal health care. Measures to prevent preterm delivery including various pharmacological agents use to inhibit uterine contractions. Nifedipine, a dihydropyridine calcium entry blocker, is an effective tocolytic agent with low toxicity and teratogenicity, while carrying potential maternal as well as fetal vascular side effects due to its action on vascular smooth muscle. This study was performed to asses nifedipine use as tocolytic agent in preventing preterm birth, and assessing maternal as well as fetal vascular side effects. This experimental study with one-group pretest-posttest design was performed in 30 pregnant women given nifedipine as tocolytic. Doppler assessment of uterine, umbilical and fetal middle cerebral arteries, ductus venosus, and cerebroplacental ratio was performed before and 48 hours after nifedipine therapy. Wilcoxon's signed ranks test was used to analyze the difference between the two variables. A P-value of < 0.05 was considered significant. The result of the study showed nifedipine was associated with a significant decreased of pulsatility index uterine artery (p = 0.016; p-value<0.05) and umbilical artery (p = 0.037; p-value<0.05) after 48 hours therapy, while pulsatility index of fetal middle cerebral arteries, ductus venosus, and cerebroplacental ratio did not change significantly. The study concluded that nifedipine is an effective tocolytic. Administration of nifedipine can increase uteroplacental blood flow, increase fetal blood flow, no redistribution of cerebral blood flow, and no changes in venous fetal blood flow. So, nifedipine is harmless for the fetus.