Postpartum bleeding
Postpartum bleeding or postpartum hemorrhage (PPH) is often defined as the loss of more than 500 ml or 1,000 ml of blood following childbirth.[2] Some have added the requirement that there also be signs or symptoms of low blood volume for the condition to exist.[6] Signs and symptoms may initially include: an increased heart rate, feeling faint upon standing, and an increased breathing rate.[1] As more blood is lost, the patient may feel cold, blood pressure may drop, and they may become restless or unconscious.[1] In severe cases circulatory collapse, disseminated intravascular coagulation and death can occur. The condition can occur up to twelve weeks following delivery in the secondary form.[7] The most common cause is poor contraction of the uterus following childbirth.[2] Not all of the placenta being delivered, a tear of the uterus, or poor blood clotting are other possible causes.[2] It occurs more commonly in those who already have a low amount of red blood, are Asian, have a larger fetus or more than one fetus, are obese or are older than 40 years of age.[2] It also occurs more commonly following caesarean sections, those in whom medications are used to start labor, those requiring the use of a vacuum or forceps, and those who have an episiotomy.[2][8]
Postpartum bleeding
Postpartum hemorrhage
Significant blood loss after childbirth, increased heart rate, feeling faint upon standing, increased breath rate[1][2]
Poor contraction of the uterus, not all the placenta removed, tear of the uterus, poor blood clotting[2]
Anemia, Asian ethnicity, more than one baby, obesity, age older than 40 years[2]
Intravenous fluids, non-pneumatic anti-shock garment, blood transfusions, ergotamine, tranexamic acid[2][3]
3% risk of death (developing world)[2]
83,100 (2015)[5]
100% rates of prevention are achieved at vaginal births by expediently delivering the placenta in squat position by 3 minutes postpartum.[9]
Other means of prevention involve decreasing known risk factors including procedures associated with the condition, if possible, and giving the medication oxytocin to stimulate the uterus to contract shortly after the baby is born.[2] Misoprostol may be used instead of oxytocin in resource-poor settings.[2] Treatments may include: intravenous fluids, blood transfusions, and the medication ergotamine to cause further uterine contraction.[2] Efforts to compress the uterus using the hands may be effective if other treatments do not work.[2] The aorta may also be compressed by pressing on the abdomen.[2] The World Health Organization has recommended the non-pneumatic anti-shock garment to help until other measures such as surgery can be carried out.[2] Tranexamic acid has also been shown to reduce the risk of death,[3] and has been recommended within three hours of delivery.[10]
In the developing world about 1.2% of deliveries are associated with PPH and when PPH occurred about 3% of women died.[2] It is responsible for 8% of maternal deaths during childbirth in developed regions and 20% of maternal deaths during childbirth in developing regions.[7] Globally it occurs about 8.7 million times and results in 44,000 to 86,000 deaths per year making it the leading cause of death during pregnancy.[4][2][11] About 0.4 women per 100,000 deliveries die from PPH in the United Kingdom while about 150 women per 100,000 deliveries die in sub-Saharan Africa.[2] Rates of death have decreased substantially since at least the late 1800s in the United Kingdom.[2]
Definition[edit]
Depending on the source, primary postpartum bleeding is defined as blood loss in excess of 500 ml following vaginal delivery or 1000 mL following caesarean section in the first 24 hours following birth. Others have defined the condition as blood loss of greater than 1000 mL after either delivery method, or any amount of blood loss with signs and symptoms of hypovolemia.[7] Secondary postpartum bleeding is that which occurs after the 24 hours up to 12 weeks after childbirth.[7]
Signs and symptoms[edit]
Symptoms generally include heavy bleeding from the vagina that doesn't slow or stop over time.[12] Initially there may be an increased heart rate, feeling faint upon standing, and an increased respiratory rate.[1] As more blood is lost, the patient may feel cold, blood pressure may drop, and they may become unconscious.[1]
Signs and symptoms of circulatory shock may also include blurry vision, cold and clammy skin, confusion, and feeling sleepy or weak.[1][12]
Causes of postpartum hemorrhage are uterine atony, trauma, retained placenta or placental abnormalities, and coagulopathy, commonly referred to as the "four Ts":[13]
Other risk factors include endometriosis,[15] obesity, fever during pregnancy, bleeding before delivery, and heart disease.[8]
Prevention[edit]
Oxytocin is typically used right after the delivery of the baby to prevent PPH.[2] Misoprostol may be used in areas where oxytocin is not available.[2] Early clamping of the umbilical cord does not decrease risks and may cause anemia in the baby, and thus is usually not recommended.[2]
Active management of the third stage is a method of shortening the stage between when the baby is born and when the placenta is delivered.[16] This stage is when the mother is at risk of having a PPH. Active management involves giving a drug which helps the uterus contract before delivering the placenta by a gentle but sustained pull on the umbilical cord whilst exerting upward pressure on the lower abdomen to support the uterus (controlled cord traction).[16]
Active management of the third stage of labor with uterotonics (oxytocin or Misoprostol) and gentle umbilical cord traction have been shown to reduce the incidence of PPH by 66%.[7]
Another method of active management which is no longer recommended is fundal pressure during the delivery of the placenta. A review into this method found no benefit to its use and advises only controlled cord traction because fundal pressure can cause the mother unnecessary pain.[16] Allowing the cord to drain appears to shorten the third stage and reduce blood loss but evidence around this subject is not strong enough to draw solid conclusions.[17]
Nipple stimulation and breastfeeding triggers the release of natural oxytocin in the body, therefore it is thought that encouraging the baby to suckle soon after birth may reduce the risk of PPH for the mother.[18] A review looking into this did not find enough good research to say whether or not nipple stimulation did reduce PPH. More research is needed to answer this question.[18]
Epidemiology[edit]
Methods of measuring blood loss associated with childbirth vary, complicating comparison of prevalence rates.[57] A systematic review reported the highest rates of PPH in Africa (27.5%), and the lowest in Oceania (7.2%), with an overall rate globally of 10.8%.[57] The rate in both Europe and North America was around 13%.[57] The rate is higher for multiple pregnancies (32.4% compared with 10.6% for singletons), and for first-time mothers (12.9% compared with 10.0% for women in subsequent pregnancies).[57] The overall rate of severe PPH (>1000 ml) was much lower at an overall rate of 2.8%, again with the highest rate in Africa (5.1%).[57]