Name a common tocolytic drug used in the management of preterm labor.

• A. Indomethacin
• B. Nifedipine
• C. Terbutaline
• D. Magnesium sulfate

Answer: (C)

To delay preterm birth, tocolytics are used to quiet uterine contractions so there’s time for fetal maturation and delivery planning. Terbutaline works by stimulating beta-2 receptors in the uterine smooth muscle, which raises cyclic AMP and lowers intracellular calcium. This chain of events relaxes the uterus and reduces contractions, making it a fast-acting option to halt preterm labor when needed. It’s often given by subcutaneous or intravenous routes for quick effect, used for short-term tocolysis with careful monitoring for maternal side effects such as tachycardia, palpitations, and other beta-adrenergic effects. Other agents like indomethacin and nifedipine are also used tocolytics and magnesium sulfate has roles in neuroprotection and sometimes tocolysis, but terbutaline is a classic, commonly employed choice for stopping preterm contractions.