Final answer:
Two beta2 agonists commonly used in labor are Terbutaline and Salbutamol, which relax the smooth muscle of the uterus.
Step-by-step explanation:
Two beta2 agonists commonly used in labor are Terbutaline and Salbutamol. These drugs are used to relax the smooth muscle of the uterus, which can help in delaying or stopping preterm labor contractions. Terbutaline is typically administered as an injection, while Salbutamol is often given through an inhaler.