A study of indomethacin combined with ritodrine in threatened preterm labor.

A prospective and double-blind study was undertaken to compare the effectiveness of two different treatments on two randomized groups of patients with threatened preterm labor. The first treatment consisted of the administration of ritodrine and a placebo; in the second, ritodrine was combined with indomethacin. 22 patients were evaluated in each group. The results obtained for gain in days, number of patients delivered at term, weight of newborns and number of recurrences in each group suggest that treatment with ritodrine and indomethacin is slightly but significantly more effective than treatment with ritodrine and placebo in prolonging pregnancy. No evidence has been found of possible unfavorable vascular effects of indomethacin in the fetus or the newborn.