A randomized comparison of nifedipine and ritodrine for suppression of preterm labor. A comparison of tocolysis with nifedipine or ritodrine: analysis of efficacy and maternal, fetal, and neonatal outcome. Efficacy and safety of nifedipine versus magnesium sulfate in the management of preterm labor: a randomized study. Nicardipine versus salbutamol in the treatment of premature labor. A prospective randomized study. Comparison of nifedipine and ritodrine for the treatment of preterm labor. The use of a calcium antagonist (nifedipine) to suppress preterm labour. Nifedipine versus terbutaline in management of preterm labor. [A randomized study of the treatment of threatened premature labor. Nifedipine versus ritodrine]. Nifedipine and ritodrine in the management of preterm labor: a randomized multicenter trial. A prospective, randomized trial of nifedipine vs. ritodrine in threatened preterm labor. Nifedipine versus ritodrine for suppression of preterm labour. Oral nicardipine versus intravenous magnesium sulfate for the treatment of preterm labor.
To compare the efficacy and safety of nifedipine and ritodrine in preventing preterm labor, and to evaluate maternal side effects and neonatal outcome.
                Non-blind, randomized controlled trial
                A randomized trial of 102 pregnant women with gestational ages under 34 weeks, including 24 with twin pregnancies and 45 on betasympathicomimetic drugs, who had regular uterine contractions with either observed cervical changes or preterm rupture of membranes. After stratification women were randomly assigned to receive either ritodrine intravenously or nifedipine orally. Fifty-five women were randomized to the nifedipine group and 47 to the ritodrine group. As expected, both groups were comparable in terms of several entry variables, including mean gestational age, ruptured membranes, treatment with tocolytic drugs, cervical examination, contraction frequency, age, and twin gestation. Delivery of women in the nifedipine group was delayed for 48 h, 7 days, and until 34 weeks gestation in 33 (60%), 26 (47%) and 21(38%) cases, respectively, compared with 31 (66%), 21(45%) and 11(23%) women in the ritodrine group (no significant difference). Maternal side effects were significantly less common in the nifedipine group than in the ritodrine group, however after 7 days of therapy there was no difference between the two groups. Neonatal outcome was similar in the two groups, with four neonatal deaths in the nifedipine and five in the ritodrine group.
                Nifedipine seems to be as effective as ritodrine in the treatment of preterm labor and is associated with less frequent side effects. Nifedipine, a dihydropyridone calcium entry blocker, has been used with increasing frequency in the treatment of preterm labor. We studied 66 patients in this prospective, randomized trial to evaluate the efficacy and maternal, fetal, and neonatal outcome associated with tocolysis with nifedipine or ritodrine. Delivery was delayed for 48 hours, 7 days, and until the thirty-sixth week of gestation in 84%, 70%, and 41%, respectively, of patients in the nifedipine group, compared with 72%, 63%, and 52% of patients in the ritodrine group (difference not significant). Maternal side effects were more common and more serious in the group of patients who received ritodrine compared with those who received nifedipine (18 of 38 versus 5 of 38, p less than 0.01); however, fetal and neonatal outcome appeared to be similar when the groups were compared. On the basis of this study, it appears that tocolysis with either nifedipine or ritodrine is equally efficacious; however, maternal side effects are less common with nifedipine treatment. We conclude that nifedipine may have a role in the treatment of preterm labor but suggest further careful evaluation of this agent before it is considered for routine clinical use. Our purpose was to establish the efficacy and safety of nifedipine versus magnesium sulfate in arresting preterm labor and the efficacy of nifedipine versus terbutaline in preventing recurrent labor.
                Singleton pregnancies at < 34 weeks in preterm labor were randomized to either oral nifedipine or intravenous magnesium sulfate. In case of tocolysis failure ritodrine was added. After labor was arrested, the patients in the nifedipine group were maintained on oral nifedipine, and those in the magnesium sulfate group were treated with oral terbutaline until completing 34 weeks.
                Of 100 patients 80 were considered eligible, of whom 39 were randomized to the nifedipine group. Both groups were comparable in terms of a number of entry variables, including cervical examination, contraction frequency, and gestational age. Both drugs were equally effective in arresting labor and delaying delivery > 48 hours, 92% versus 93%. Both study groups had a similar incidence of side effects, although four (10%) of magnesium sulfate-treated patients required drug discontinuation because of severe symptoms. Nifedipine was as effective as terbutaline in preventing recurrent labor, 26% versus 24%, and in achieving a gestation > 34 weeks, 62% versus 68%.
                Oral nifedipine is as effective as magnesium sulfate and terbutaline in arresting and preventing idiopathic preterm labor. To compare the tocolytic action and the side effects of nicardipine to those of salbutamol in patients presenting premature labor in order to propose nicardipine as a promising alternative to salbutamol in the treatment of premature labor.
                Ninety patients admitted to the Saint-Antoine Hospital (Paris, France) for premature labor were included in this prospective randomized open study comparing nicardipine and salbutamol. Each study group included 45 patients.
                The mean term of delivery in the nicardipine group was 38.4 +/- 1.7 and 37.6 +/- 2.1 weeks in the salbutamol group (P < 0.05). The percentage of deliveries after 37 gestational weeks was higher with nicardipine (P < 0.05). The birthweight of infants was 3131 +/- 488 g with patients treated with nicardipine and 3019 +/- 494 g with the salbutamol group (NS). The Apgar scores were identical in the two groups at 1 and 5 min. There was no statistically significant difference in the number of neonates admitted into intensive care nor the premature infant center between the two groups. Nicardipine reduced the systolic and diastolic blood pressure whereas there was no change in the salbutamol group. Maternal pulse rate was significantly increased in the salbutamol group (P < 0.01) and was unchanged in the nicardipine group. The most common side-effects with nicardipine were headaches, and with salbutamol, tremors and palpitations.
                Nicardipine is a tocolytic agent as effective as salbutamol in the treatment of premature labor. The use of nicardipine is an interesting alternative to salbutamol, especially in cases of hypertension, diabetes or maternal cardiopathy. Treatment of preterm labor with beta-sympathomimetics has been questioned because of the many maternal and fetal complications associated with its use. Nifedipine, a calcium antagonist, has been shown to suppress uterine activity in vitro and in vivo. A randomized prospective study was performed to compare the efficacy of nifedipine to ritodrine in the suppression of preterm labor. Data obtained from 42 women, of which 19 were randomized to the ritodrine group and 23 to the nifedipine group, were analyzed. Ritodrine and nifedipine proved to be equally effective in the suppression of preterm labor. However, the nifedipine group had fewer maternal and fetal complications. The efficacy of an orally administered calcium antagonist, nifedipine, in suppressing premature uterine activity, was compared with intravenous ritodrine and no treatment. Nifedipine was found to be significantly more effective than ritodrine or withholding therapy, and was almost devoid of side-effects. nan The authors compare the efficiency of two drugs in the treatment of threatened premature labour, the one being the calcium inhibitor (nifedipine) and the other a beta-mimetic drug (ritodrine). 62 patients after random selection were divided into two groups: 32 treated with ritodrine and 30 treated with nifedipine. The treatment was carried out over 7 days. The success rate was similar in both groups -72% for the ritodrine group and 63.33% for the nifedipine group. Women receiving nifedipine had slightly greater gain in weeks, six as against five for ritodrine. The side effects which were often found with nifedipine were; hot flushes (in 10 cases) and headaches (4 cases). These symptoms appeared 15-30 minutes after the first dose and were transitory. No neonatal complications were found. The ease with which a calcium inhibitor can be given suggests that it should be used more frequently in the treatment of threatened premature labour and particularly when there are contra-indications to the use of beta-mimetic drugs. To compare the efficacy of nifedipine with ritodrine in the management of preterm labor.
                One hundred eighty-five singleton pregnancies with preterm labor were assigned randomly to either ritodrine intravenously (n = 90) or nifedipine orally (n = 95). The principal outcome assessed was delay of delivery.
                Ritodrine was discontinued in 12 patients because of severe maternal side effects, and their results were excluded from further analysis. More women in the ritodrine group delivered within 24 hours (22 versus 11, P = .006), within 48 hours (29 versus 21, P = .03), within 1 week (45 versus 36, P = .009), and within 2 weeks (52 versus 43, P = .005) compared with those receiving nifedipine. There were significantly fewer maternal side effects in the nifedipine group. Apgar scores and umbilical artery and vein pHs were similar in both groups. The number of admissions to the neonatal intensive care unit (NICU) in the nifedipine group was significantly lower than in the ritodrine group (68.4 versus 82.1%, P = .04).
                Nifedipine in comparison with ritodrine in the management of preterm labor is significantly associated with a longer postponement of deliver, fewer maternal side effects, and fewer admissions to the NICU. To compare the tocolytic efficacy and maternal tolerance of nifedipine with ritodrine in the management of threatened preterm labor.
                Prospective randomized study of 52 singleton pregnancies with preterm labor between 26 and 34 week's gestation. The capacity to delay delivery 48 h, 7 days, until week 36 or until fetal weight reached 2500 g were the outcome variables assessed. Doppler ultrasound studies were performed on the fetal umbilical artery as control.
                No significant differences were found in the delay of delivery, but significantly fewer maternal side-effects were found in the nifedipine group. Doppler ultrasound results were similar in both groups.
                Nifedipine is a valid and well-tolerated alternative among the tocolytic drugs, and apparently does not significantly alter fetal vascular blood flow. To compare the efficacy of tocolysis with specific regimens of nifedipine and ritodrine. Maternal side effects and neonatal outcome also were evaluated.
                A prospective, randomised trial.
                Seventy-one women, including 11 with twin pregnancies, who had uterine contractions and observed cervical changes.
                Prolongation of pregnancy for 48 h, seven days and until 36 weeks of pregnancy were evaluated for each treatment. Maternal side effects and haemodynamic changes were compared, as well as neonatal outcomes.
                Delivery was delayed for 48 h, seven days, and until the 36th week of gestation in 83%, 67%, and 50%, respectively, of women in the nifedipine group, compared with 77%, 63% and 43%, respectively, of women in the ritodrine group (no significant difference). Maternal side effects were significantly less common in the ritodrine group (no significant difference). Maternal side effects were significantly less common in the nifedipine group (27%) than in the ritodrine group (77%) (P < 0.001). The neonatal outcome was similar in the two groups. The fall in mean arterial and diastolic blood pressure, and the rise in maternal heart rate were significantly greater in the women who received ritodrine compared with those treated with nifedipine.
                Nifedipine is as effective as ritodrine in suppressing preterm labour. Its use is associated with less frequent side effects. The aim of this study was to compare the efficacy and safety of oral nicardipine in acute therapy for preterm labor with those of parenteral magnesium sulfate.
                Patients between 24 and 34 weeks' gestation with documented preterm labor were randomly assigned to receive oral nicardipine (n = 57) or intravenous magnesium sulfate (n = 65) as initial tocolytic therapy. Patients in the nicardipine group received a 40-mg loading dose and then 20 mg every 2 hours as needed to stop contractions (total 80 mg). Patients in the magnesium sulfate group received a 6-g bolus followed by 2 to 4 g/h to provide uterine quiescence. Patients could be switched to another tocolytic regimen if they continued to have contractions after 6 hours of therapy. The main outcome variables examined were time to uterine quiescence, time gained in utero, recurrence of preterm labor, failure of tocolysis, and pertinent maternal and neonatal outcomes.
                There were no significant differences in maternal demographic characteristics between the groups. Among patients who responded with uterine quiescence within 6 hours, there was a significant decrease in the time to uterine quiescence in the nicardipine group (P <.01). Patients in the magnesium sulfate group were more likely to have recurrence of preterm labor necessitating further tocolytic attempts (P =.048). The patients in the magnesium sulfate group had more adverse side effects, mainly nausea and vomiting (P =.004). There were no differences in birth weight, estimated gestational age at delivery, or neonatal complications between the 2 groups.
                Oral nicardipine is an effective, safe, and well-tolerated tocolytic agent. In this prospective clinical trial patients randomly assigned to receive oral nicardipine had arrest of preterm labor more rapidly than did those randomly assigned to receive parenteral magnesium sulfate. Patients who received magnesium sulfate were more likely to have adverse medication effects and recurrent preterm labor.