Ritodrine, commonly known as Ampro, is a beta-adrenergic receptor agonist with high selectivity for β2 receptors in uterine smooth muscle, which binds to it to relax uterine smooth muscle and thus inhibit contractions. Its main side effects include palpitations, chest tightness, tachycardia, facial flushing, nausea, vomiting, tremor and nervousness, etc. Serious adverse effects are pulmonary edema, especially when glucocorticoids are used in combination to avoid neonatal respiratory distress. It should not be used in the first 16 weeks of pregnancy and when the cervix is dilated more than 4 cm. During intravenous infusion, the mother’s blood pressure, pulse, respiration and fetal heart rate should be closely monitored.