Postpartum bleeding

Postpartum bleeding or postpartum hemorrhage (PPH) is significant blood loss following childbirth. It is the most common cause of maternal death worldwide, disproportionately affecting developing countries.^[6] Definitions and criteria for diagnosis are highly variable.^[2][7] PPH is defined by the World Health Organization as "blood loss of 500 ml or more within 24 hours after birth",^[8] though signs of shock (insufficient blood flow) have also been used as a definition.^[7] Some bleeding after childbirth is normal and is called lochia. It is difficult to distinguish lochia from delayed PPH.^[9]

Signs and symptoms of PPH may initially include: an increased heart rate, feeling faint upon standing, and an increased breathing rate. 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.^[10]

The most common cause of PPH is insufficient contraction of the uterus following childbirth; this contraction normally stops the blood flow that supplies the fetus during pregnancy. Other causes are retained placenta, where the placenta is not expelled after childbirth; a tear of the uterus, cervix, or vagina; or poor blood clotting. PPH is more likely to occur in people who are Asian, are obese, previously had PPH or have an anemia, give birth to a large baby or more than one fetus, 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][11]

Prevention involves 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,^[12] and has been recommended within three hours of delivery.^[13]

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.^[10] 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][14] 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]