Key messages

• Uterotonics (medications used to cause contractions of the womb) may be no more effective than placebo (pretend treatment) or no treatment in avoiding manual removal of the placenta (removal of the placenta by inserting a hand into the womb), and probably do not reduce severe bleeding or need for a blood transfusion (where blood is taken from a donor and injected into the person who has lost a lot of blood).

• Different types of these medications probably make little to no difference in avoiding manual removal of the placenta and may not reduce the need for a blood transfusion.

• More research is needed to determine the best way to manage a retained placenta.

What is a retained placenta?

The placenta forms in the womb during pregnancy to provide oxygen and nutrients to the baby through the blood vessels in the umbilical cord. Normally, the placenta is delivered shortly after the baby is born. A retained placenta occurs when the placenta does not come out on its own within 30 to 60 minutes after delivery of the baby. This can cause dangerous bleeding for the mother.

What did we want to find out?

We wanted to know if using uterotonics (which cause the womb to contract; for example, misoprostol, carbetocin, and oxytocin) could help deliver a retained placenta without the woman needing surgery. We also wanted to see if these medications reduced complications like heavy bleeding or the need for blood transfusions (where blood is taken from a donor and injected into the person who has lost a lot of blood).

What did we do?

We searched for studies that compared different uterotonic medications to each other, to placebo, or to no treatment for retained placenta. We looked at and summarised the results, then rated how confident we were in the evidence by considering things like the study methods and the number of people.

What did we find?

We found five studies that involved 560 women with retained placenta. In four studies, women were assigned randomly to two or three treatment groups, and in one study, women were not randomly placed into different treatment groups. The studies focused on women in late pregnancy.

Main results

• Uterotonics may be no more effective than placebo or no treatment in reducing the need for manual removal of the placenta, and probably make little to no difference to severe bleeding or need for blood transfusions. We are not sure how these medications affect the amount of blood loss.

• We are not sure about the effect of misoprostol on shivering (an unwanted effect of blood loss).

• Carbetocin into a vein (blood vessel) probably does not reduce the need for manual removal of the placenta and may not reduce the need for a blood transfusion compared to misoprostol given under the tongue.

• Misoprostol given under the tongue probably makes little to no difference to the need for manual removal of the placenta and may not reduce the need for a blood transfusion compared to oxytocin into a vein in the umbilical cord.

• Carbetocin into the vein probably does not reduce the need for manual removal of the placenta and may make little to no difference to reducing blood transfusions compared to oxytocin into a vein in the umbilical cord.

• We do not know whether giving oxytocin into the vein has an effect on the need for manual removal of the placenta compared to oxytocin into a vein in the umbilical cord.

What are the limitations of the evidence?

Our confidence in the evidence varied from none to moderate, meaning future research could change our conclusions. Three main factors reduced our confidence in the evidence. First, many of the studies had problems with how they were designed or conducted, which affects how reliable their results are. For example, it is possible that women in the studies were aware of which treatment they were getting. Second, results were very varied across the different studies. Finally, we only found a few studies and some of these were very small with relatively few women.

How up to date is this evidence?

This evidence is current to 25 April 2024.