All About Uterotonics
What are uterotonics?
Uterotonic drugs are uterine stimulants that promote contractions of the uterus and can be administered to induce labor or prevent postpartum hemorrhage (PPH). Common uterotonics include oxytocin and misoprostol.
Why are they important?
Almost all maternal deaths occur in low-resource settings because women in these settings do not always have access to skilled care during childbirth or adequate emergency care following childbirth.
PPH is the leading cause of maternal death. It occurs once a woman has lost more than half a liter of blood following childbirth. If the bleeding remains uncontrolled, the mother’s blood pressure dips to dangerously low levels and her risk of death from shock increases dramatically.
How are uterotonics used to prevent PPH?
Uterotonics prevent PPH by stimulating uterine contractions, which cause the bleeding to slow in the arteries of the uterus. Slow arterial blood flow combined with the damaged arteries in the placental bed cause blood in the uterus to clot. Because uterotonics have proven effective against severe bleeding after delivery, the World Health Organization (WHO) recommends that uterotonic drugs be offered to all women immediately after childbirth during “active management” of the third stage of labor.
Which are the most commonly used drugs?
Oxytocin halves the risk of PPH and reduces the risk of severe PPH. (1) However, oxytocin requires refrigeration to keep it fresh. In many low resource areas, refrigeration is not available. Additionally, oxytocin requires sterile equipment and a skilled provider to administer the drug, two obstacles in regions where only half of births take place in the presence of a skilled birth attendant. Even though oxytocin has its disadvantages, it still remains the first choice of all the uterotonic drugs and has fewer side effects.
Misoprostol can be used when oxytocin is unavailable. (2) Administration of misoprostol is inherently more applicable to low-tech settings, as it does not require refrigeration to keep fresh, can be given orally to mothers by community health workers, and is less expensive. (3) Studies have shown that misoprostol can diminish the frequency PPH. Side effects include shivering and fever.
The WHO will begin a clinical study in June to test the effectiveness of a new formulation of carbetocin, an oxytocin-like drug developed by Ferring Pharmaceuticals to prevent PPH. (4) Unlike oxytocin, the new drug is stable at room temperature and in hot, tropical climates. If the clinical trial is successful, Merck for Mothers, Ferring, and WHO will collaborate to make the drug available to the developing world at a lower price than current uterotonics.
Carnemark, Curt / World Bank. 2008. Portrait of women and children. [Photograph]. Retrieved from https://www.flickr.com/photos/worldbank/2244548984/in/set-72157603947778876/.*
1. Abalos E. Choice of uterotonic agents in the active management of the third stage of labour: RHL commentary (last revised: 2 March 2009). The WHO Reproductive Health Library; Geneva: World Health Organization.
2. Gizzo S, Patrelli TS, Gangi SD, et al. Which uterotonic is better to prevent the postpartum hemorrhage? Latest news in terms of clinical efficacy, side effects, and contraindications: a systematic review. Reprod Sci. 2013;20:1011–1019.
3. POPPHI. Fact sheets: Uterotonic drugs for the prevention and treatment of postpartum hemorrhage. Seattle: PATH; 2008.
4. Merck and Ferring Pharmaceuticals. Merck, Ferring Pharmaceuticals and the World Health Organization working together to prevent excessive bleeding in women after childbirth. [Press Release]. 2014 April [cited 2014 April 28]. Available from http://www.businesswire.com/news/home/20140404005156/en/Merck-Ferring-Pharmaceuticals-World-Health-Organization-Working#.U2PFeleeb3U.
*In no way does the licensor of this image endorse SCIWHF, the content of this post, or the use of this image on this website.