A RANDOMIZED COMPARISON OF NIFEDIPINE AND RITODRINE FOR SUPPRESSION OF PRETERM LABOR

Objectives. To compare the efficacy and safely of nifedipine and ritod rine in preventing preterm labor, and to evaluate maternal side effect s and neonatal outcome. Study design. Non-blind, randomized controlled trial Results. A randomized trial of 102 pregnant women with gestatio nal 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. Aft er stratification women were randomly assigned to receive either ritod rine intravenously or nifedipine orally. Fifty-five women were randomi zed to the nifedipine group and 47 to the ritodrine group. As expected , both groups were comparable in terms of several entry variables, inc luding mean gestational age, ruptured membranes, treatment with tocoly tic drugs, cervical examination, contraction frequency, age, and twin gestation. Delivery of women in the nifedipine group was delayed for 4 8 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 si de 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 t he ritodrine group. Conclusions. Nifedipine seems to be as effective a s ritodrine in the treatment of preterm labor and is associated with l ess frequent side effects. (C) 1998 Elsevier Science Ireland Ltd.