If a pregnant woman is showing signs of preterm labor, her doctor will often try treatments to stop labor and prolong the pregnancy until the fetus is more fully developed. Treatments include therapies to try to stop labor (tocolytics) and medications administered before birth to improve outcomes for the infant if born preterm (antenatal steroids to improve the respiratory outcomes and neuroprotective medications such as magnesium sulfate).
Medications to Delay Labor
Drugs called tocolytics (pronounced toh-coh-LIT-iks) can be given to many women with symptoms of preterm labor. These drugs can slow or stop contractions of the uterus and may prevent labor for 2 to 7 days. One common treatment for delaying labor is magnesium sulfate (pronounced mag-NEEZ-ee-um SUL-fate), given to the pregnant woman intravenously through a needle inserted in an arm vein.
Medications to Speed Development of the Fetus
Tocolytics may provide the extra time for treatment with corticosteroids (pronounced kohr-tuh-koh-STER-oids) to speed up development of the fetus's lungs and some other organs or for the pregnant woman to get to a hospital that offers specialized care for preterm infants. Corticosteroids can be particularly effective if the pregnancy is between 24 and 34 weeks (between 5½ and 7¾ months) and the woman's health care provider suspects that the birth may occur within the next week.1 Intravenously delivered magnesium sulfate may also reduce the risk of cerebral palsy if the child is born early.2