[Management of preterm labor]

The main purpose of using uterulytic in preterm delivery is to prolong gestation in order to allow the administration of glucocorticoid to the mother and/or to accomplish the mother's transference to a tertiary hospital center. Decisions on uterolytic use and choice require correct diagnosis of preterm delivery, as well as the knowledge of gestational age, maternal-fetal medical condition, and medicine's efficacy, side-effects and cost. All the uterolytics have side-effects, and some of them are potentially lethal. Studies suggest that beta-adrenergic receptor agonists, calcium blockers and cytokine receptor antagonists are effective to prolong gestation for at least 48 hours. Among these three agents, atosiban (a cytokine receptor antagonist) is safer, though it presents a high cost. Magnesium sulfate is not efficient to prolong gestation and presents significant side-effects. Cyclooxygenase inhibitors also present significant side-effects. Up till now, there is not enough evidence to recommend the use of nitric oxide donors to inhibit preterm delivery. There is no basis for the use of antibiotics to avoid prematurity in face of preterm labor.