Final answer:
To stop preterm labor, a physician would prescribe tocolytics, which are designed to delay labor by suppressing uterine contractions.
Step-by-step explanation:
The question pertains to the management of preterm labor in a pregnant woman, Mrs. Garcia, who is experiencing contractions. In such a medical scenario, a physician would prescribe tocolytics. Tocolytics are medications that aim to suppress uterine contractions, thereby delaying preterm labor. These medicines are in contrast to oxytocics, which are used to induce labor by strengthening contractions, primarily through the effects of the hormone oxytocin. It is important to note that estrogen, while it prepares the uterus for labor by increasing sensitivity to oxytocin, is not used in managing preterm labor. Similarly, prostaglandins are natural compounds that promote labor, making them unsuitable for halting preterm labor.