Myocardial necrosis in a newborn after long-term maternal subcutaneous terbutaline infusion for suppression of preterm labor

A number of drugs are now in use to prevent preterm labor. Terbutaline, a beta-sympathomimetic agent, is used for long-term suppression of labor. Previously, no complications to either the mother or fetus have been reported from use of this drug. The case is reported of a newborn who had myocardial tissue damage thought to be caused by terbutaline. Drug therapy to prevent premature labor was begun at 25 weeks' gestation. The mother received a continuous infusion of terbutaline under the skin until the infant was born at 37 weeks of pregnancy. The infant appeared normal until his breathing rate became very rapid. Cardiac abnormalities were detected and the infant was treated for congestive heart failure. A biopsy of tissue taken from the right ventricle showed myocardial fiber degeneration. No infectious or metabolic cause of this degeneration could be found. The infant recovered and developed normally. Long-term therapy with this drug is relatively new. In another study, heart autopsies performed on infants who died from being born prematurely and whose mothers received these types of drugs showed myocardial necrosis. The effects of long-term use of terbutaline on the fetal heart are clearly in need of further evaluation. (Consumer Summary produced by Reliance Medical Information, Inc.)