Treatment of Preterm Labor: Progesterone & Nitroglcyerin Health Article

Progesterone and Related Drugs

Progesterone is one of the main hormones produced during pregnancy. In the past, progesterone-related drugs were widely used in women who were considered at risk for miscarriage or preterm birth. The most commonly used substance was 17-alpha hydroxyprogesterone caproate.

In two recent studies, women who received progesterone injections or suppositories had fewer preterm births than women who did not get the medication. All of the women in these studies had had an early delivery in the past, or were considered at very high risk of delivery too soon. Other studies have not shown that progesterone is helpful. Importantly, no studies have shown that progesterone can stop preterm labor once contractions have started. You should meet with a high-risk obstetrician to discuss whether progesterone might be helpful in your pregnancy.

Nitroglycerin

Nitroglycerin relaxes smooth muscle. Because the uterus is made up mainly of smooth muscle, nitroglycerin could be used to treat premature labor. At the present time, though, this treatment is considered highly unusual and further study is needed.

The drug is available in many forms, including sublingual (under the tongue) tablets or aerosol, skin patches, ointment, and intravenous (IV) drip. The drug works very quickly (when given IV, nitroglycerin relaxes the uterus within 45 to 75 seconds) and for a very short period of time (about two minutes). An extended release oral capsule is also available.

Several researchers have studied nitroglycerin and related drugs for preterm labor. Nitroglycerine was not any more effective than magnesium, and several women developed dangerously low blood pressures while using the medication. For now, these drugs shouldn't be used for preterm labor unless they are part of a research study.

For information about other tocolytic drugs, go to:

• Treatment of Preterm Labor: Terbutaline,
• Treatment of Preterm Labor: Magnesium Sulfate,
• Treatment of Preterm Labor:Calcium Channel Blockers, or
• Treatment of Preterm Labor: NSAIDs Indomethacin.

For more information on treatments that could reduce your baby's risk of problems if he or she arrives early, go to Treatment of Preterm Labor: Steroids & Antibiotics.