Uterine atony is a condition in which the muscles of a woman's uterus lose their tone and their ability to contract after childbirth. Severe hemorrhaging and low blood pressure can result, presenting a number of additional health problems. Women who spend several hours in labor, deliver large or multiple babies, or have had several pregnancies in the past are at the highest risk of developing uterine atony. Doctors usually take several precautions to prevent the condition during labor, though complications can still occur. Treatment for uterine atony includes intravenous medications, massage techniques to stimulate contractions, and emergency surgery to stop excessive blood loss.

A woman's uterine muscles usually contract to stop bleeding after the baby and the placenta are delivered. The muscles work to constrict exposed blood vessels, stopping the flow of blood and repairing uterine walls. Uterine atony causes the uterus to relax and stops the muscles from contracting regularly. Unrestricted blood vessels can release huge amounts of blood, leading to severe hemorrhages and hypotension.

Many different factors can contribute to insufficient muscle contractions and uterine atony. Women who experience long, difficult childbirths can develop the condition due to the overexertion of uterine muscles. Giving birth to twins or a larger than average baby may cause muscles to stretch beyond their limits, leaving them limp and unable to contract properly. Individuals may also have problems if they have delivered many babies in the past, usually more than four. The condition may also occur due to the numbing effects of anesthesia, a severe infection, or medications that relax muscles as a side effect.

Attending doctors and nurses usually try to take preventative measures during childbirth to avert hemorrhaging and uterine atony. A doctor might try to take strain off of the uterine muscles by guiding a baby out with his or her hands. At-risk women are frequently given synthetic oxytocin, a chemical that supplements natural hormones to help the uterus return to normal after giving birth. Doctors and nurses may also try to massage the muscles during delivery to restore proper functioning and promote contractions.

If preventative measures are not effective, doctors take immediate action to stop blood loss. The muscles are continuously massaged and additional intravenous oxytocin is administered. When uterine atony persists, a woman may need to undergo an emergency surgery. A surgeon can tie off blood vessels to prevent hemorrhaging or perform a hysterectomy, where the entire uterus is removed. In some cases, blood transfusions are necessary to restore healthy levels and blood pressure. Most women are able to recover from their symptoms with immediate treatment, though they are generally placed at a high risk of experiencing future problems with subsequent births.