Causes
The most common cause of postpartum hemorrhage is
Risk factors for uterine atony include
-
Uterine overdistention (caused by multifetal pregnancy, polyhydramnios, fetal anomaly, or an abnormally large fetus)
-
Prolonged labor or dysfunctional labor
-
Grand multiparity (delivery of ≥ 5 viable fetuses)
-
Relaxant anesthetics
-
Rapid labor
-
Intra-amniotic infection (chorioamnionitis)
Other causes of postpartum hemorrhage include
-
Lacerations of the genital tract
-
Extension of an episiotomy
-
Retained placental tissues
-
Hematoma
-
Intra-amniotic infection
-
Subinvolution (incomplete involution) of the placental site (which usually occurs early but may occur as late as 1 month after delivery)
Uterine fibroids may contribute to postpartum hemorrhage. A history of postpartum hemorrhage may indicate increased risk.
Diagnosis
Treatment
Intravascular volume is replenished with 0.9% saline up to 2 L IV; blood transfusion is used if this volume of saline is inadequate.
Hemostasis is attempted by bimanual uterine massage and IV oxytocin infusion. A dilute oxytocin IV infusion (10 or 20 [up to 80] units/1000mL of IV fluid) at 125 to 200 mL/hour is given immediately after delivery of the placenta. The drug is continued until the uterus is firm; then it is decreased or stopped. Oxytocin should not be given as an IV bolus because severe hypotension may occur.
In addition, the uterus is explored for lacerations and retained placental tissues. The cervix and vagina are also examined; lacerations are repaired. Bladder drainage via catheter can sometimes reduce uterine atony.
15-Methyl prostaglandin F2-alpha 250 mcg IM every 15 to 90 minutes up to 8 doses or methylergonovine 0.2 mg IM every 2 to 4 hours (which may be followed by 0.2 mg orally 3 to 4 times a day for 1 week) should be tried if excessive bleeding continues during oxytocin infusion; during cesarean delivery, these drugs may be injected directly into the myometrium. Oxytocin 10 units can also be directly injected into the myometrium. If oxytocin is not available, heat-stable carbetocin can be given IM instead. Prostaglandins should be avoided in women with asthma; methylergonovine should be avoided in women with hypertension. Sometimes misoprostol 800 to 1000 mcg rectally can be used to increase uterine tone.
Uterine packing or placement of a Bakri balloon can sometimes provide tamponade. This silicone balloon can hold up to 500 mL and withstand internal and external pressures of up to 300 mm Hg. If hemostasis cannot be achieved, surgical placement of a B-Lynch suture (a suture used to compress the lower uterine segment via multiple insertions), hypogastric artery ligation, or hysterectomy may be required. Uterine rupture requires surgical repair.
Blood products are transfused as necessary, depending on the degree of blood loss and clinical evidence of shock. Massive transfusion of packed red blood cells, fresh frozen plasma, and platelets in a 1:1:1 ratio can be considered after consultation with expert hematologists and the blood bank (1). Tranexamic acid can also be used if initial medical management is ineffective.
Treatment reference
-
1. American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Obstetrics: Practice Bulletin No. 183: Postpartum hemorrhage. Obstet Gynecol 130:e168–186, 2017.
Prevention
Predisposing conditions (eg, uterine fibroids, polyhydramnios, multifetal pregnancy, a maternal bleeding disorder, history of puerperal hemorrhage or postpartum hemorrhage) are identified antepartum and, when possible, corrected.
If women have an unusual blood type, that blood type is made available ahead of time. Careful, unhurried delivery with a minimum of intervention is always wise.
After placental separation, oxytocin 10 units IM or dilute oxytocin infusion (10 or 20 units in 1000 mL of an IV solution at 125 to 200 mL/hour for 1 to 2 hours) usually ensures uterine contraction and reduces blood loss.
After the placenta is delivered, it is thoroughly examined for completeness; if it is incomplete, the uterus is manually explored and retained fragments are removed. Rarely, curettage is required.
Uterine contraction and amount of vaginal bleeding must be observed for 1 hour after completion of the 3rd stage of labor.
Key Points
-
Before delivery, assess risk of postpartum hemorrhage, including identification of antenatal risk factors (eg, bleeding disorders, multifetal pregnancy, polyhydramnios, an abnormally large fetus, grand multiparity).
-
Replenish intravascular volume, repair genital lacerations, and remove retained placental tissues.
-
Massage the uterus and, if necessary, use uterotonics (eg, oxytocin, prostaglandins, methylergonovine).
-
If hemorrhage persists, consider packing, surgical procedures, and transfusion of blood products.
-
For women at risk, deliver slowly and without unnecessary interventions.
Drugs Mentioned In This Article
| Drug Name | Select Trade |
|---|---|
methylergonovine |
METHERGINE |
Tranexamic acid |
CYKLOKAPRON |
misoprostol |
CYTOTEC |
oxytocin |
PITOCIN |
