It's hard to prevent preterm labor, because it usually isn't expected. Also, it's often due to causes that aren't completely understood.
But building some healthy pregnancy habits-such as going to all of your doctor appointments and getting enough folic acid- may help prevent preterm labor and give your baby the best chance to be healthy.
Being pregnant with twins, triplets, or more increases the chances of preterm labor and problems for the babies.
If you had preterm labor in a previous pregnancy, your risk for having it again is high. Your doctor may consider giving you weekly progesterone shots during your second and third trimesters. Research shows that these shots may help lower your risk of preterm labor.3
But if you're pregnant with twins or more, progesterone treatment is generally not used to prevent preterm labor even if you had a previous preterm birth. Research has not shown that progesterone shots prevent preterm birth in women pregnant with more than one baby.4