Ritodrine hydrochloride: A betamimetic agent for use in preterm labor: II. evidence of efficacy

Irwin R. Merkatz, John B. Peter, Tom P. Barden

Research output: Contribution to journalArticle

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In a multicenter series of randomized prospective doubleblind controlled studies, ritodrine hydrochloride was compared with either ethanol or placebo in treatment of idiopathic preterm labor. When compared with controls, there was, among offspring of ritodrine-treated mothers, a significantly reduced incidence of neonatal death and respiratory distress syndrome (P<.05 in both comparisons) and a significantly higher proportion of infants achieving 36 weeks' gestation (P<.05) or birth weight greater than 2500 g (P<.05). There was also a significant improvement in gestational age at delivery (P<.05) and in the number of days gained in utero (P<.001) among ritodrine-treated patients as compared with controls. These results, coupled with a finding of generally acceptable side effects, have contributed to ritodrine's becoming the first drug approved for the treatment of preterm labor in the United States.

Original languageEnglish (US)
Pages (from-to)7-12
Number of pages6
JournalObstetrics and gynecology
Issue number1
Publication statusPublished - Jul 1980
Externally publishedYes


ASJC Scopus subject areas

  • Obstetrics and Gynecology

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