Merita O’Sullivan
Definition
Bright or dark red vaginal bleeding during the second or third trimester (>12 weeks’ gestation) is less common. It may be painless, or it may be associated with uterine contractions or severe abdominal pain. Antepartum bleeding (uterine bleeding after 20 weeks’ gestation that is unrelated to labor and delivery) occurs in 4% to 5% of pregnancies. Common causes of bleeding include:
A.Bloody show: Associated with labor (by definition, labor occurs after 20 weeks’ gestation). Vaginal discharge of mucus, which may be clear, pink, or slightly bloody.
B.Cervical insufficiency: The American Congress of Obstetricians and Gynecologists (ACOG) defines cervical insufficiency as the inability of the uterine cervix to maintain a pregnancy in the second trimester in the absence of clinical contractions, labor or both.
C.Low-lying placenta: The edge of the placenta grows into the area of the lower uterine segment located less than two centimeters from the internal cervical os.
D.Placenta previa: Implantation of the blastocyst occurs in the lower uterine segment, followed by placental growth. Eventually, the placenta may partially or completely cover the cervix.
E.Abruptio placentae: Partial or premature separation of a normally implanted placenta prior to delivery of the infant.
F.Uterine rupture: Complete uterine rupture extends through the entire uterine wall, and the uterine contents are extruded into the abdominal cavity. Incomplete rupture extends through the endometrium and myometrium, but the peritoneum remains intact. This occurs almost exclusively during labor and/or delivery.
G.Uterine dehiscence: Separation of an old surgical scar.
H.Vasa previa: The fetal blood vessels are present in the membrane covering the internal cervical os. The membranous vessels may be associated with a velamentous umbilical cord or they may connect the lobes of a bilobed placenta or the placenta and a succenturiate lobe. Rupture of the vasa previa is an obstetric emergency and may lead to fetal death.
I.Bloody discharge is not normal prior to 37 weeks’ gestation unless associated with recent sexual intercourse or pelvic exam. Light spotting or bleeding may be caused by recent sexual intercourse, preterm labor (PTL), rupture of membranes, or cervicitis. Note: The evaluation of vaginal bleeding prior to 20 weeks is similar to that in the first trimester.
Incidence
A.Placenta previa: Approximately 1:200 pregnancies, but varies worldwide and is more common in parous women.
B.Abruptio placenta: Approximately 1:250 pregnancies.
C.Uterine rupture: If uterus is unscarred, incidence is approximately 1:6,000 to 20,000 pregnancies. If uterus has a scar, the incidence varies depending on the type and location of the prior uterine incision. If the prior incision was low transverse, the incidence is approximately 0.7% to 2.0%, and if the prior incision was classical, the incidence is approximately 1% to 12%.
Pathogenesis
A.Placenta previa: The pathogenesis of placenta previa is unknown. One hypothesis is that the presence of areas of suboptimal endometrium in the upper uterine cavity caused by previous surgery or pregnancies promotes implantation of trophoblast in or toward the lower uterine segment. Another hypothesis is that a particularly large placental surface area, as in multiple gestation or in response to reduced uteroplacental perfusion, increases the likelihood that the placenta will cover or encroach upon the cervical os.
B.Abruptio placenta: Initiated by bleeding into the decidua basalis. The decidua then splits, and the placenta is sheared off, either partially or totally. Blood may move into and through the myometrium, leading to a board-like uterus.
C.Uterine rupture: May occur from uterine injury, caused by previous surgery or trauma.
Predisposing Factors
A.Placenta previa: Late fertilization with delayed implantation, previous uterine scar, advanced maternal age (AMA), multiple gestation, large placenta, previous previa, and smoking.
B.Abruptio placenta: A prior placental abruption is the strongest risk factor for abruption; the recurrence risk is increased 10- to 15-fold. Hypertension (chronic, gestational, or preeclampsia), cocaine use, trauma, high parity, sudden decompression of overdistended uterus (i.e., when membranes rupture), smoking, chorioamnionitis, abdominal trauma, and external cephalic version are other factors.
C.Uterine rupture: Multiparity, previous uterine incision, tetanic contractions, or prolonged labor, especially with excessive use of oxytocin.
Common Complaints
A.Placenta previa: Painless vaginal bleeding, usually in amounts of spotting to frank hemorrhage. Bleeding occasionally is accompanied by cramping or uterine contractions. A gush
of fluid associated with sudden onset of massive vaginal bleeding may be reported. Painless vaginal bleeding should be treated as a placenta previa until proven otherwise.
B.Abruptio placentae: Firm, tender uterus; hypertonic uterine contractions with high frequency and low amplitude are common. Typically presents with vaginal bleeding (80%), uterine tenderness (70%), and uterine contractions (35%) with or without nonreassuring fetal heart rate (FHR):
1.Marginal abruption: Vaginal bleeding may be absent or minimal and bright red; there may be some old, dark blood. Abdominal pain is usually mild.
Vaginal bleeding with abdominal pain should be treated as an abruption until proven otherwise.
2.Moderate abruption: Vaginal bleeding may be moderate or absent. Abdominal pain is usually significant and associated with contractions.
3.Severe abruption: Vaginal bleeding may be moderate, severe, or absent. Abdominal pain is severe. The patient may have a concealed placental abruption without vaginal bleeding.
C.Uterine rupture: Vaginal bleeding is moderate, severe, or absent. The patient may experience a sudden onset of extreme abdominal pain (commonly at the previous uterine scar site) or a cessation of uterine contractions. Recession of the fetal presenting part and maternal hypotension and tachycardia may occur.
D.Cervical insufficiency: A feeling of vaginal fullness or pressure; vaginal spotting or bleeding; an increased volume of watery, mucousy or brown vaginal discharge and vague discomfort in lower abdomen or back.
Other Signs and Symptoms
A.External fetal monitor (EFM) tracings: May exhibit characteristics that are associated with anemia or hypoxemia, such as decreased or absent variability, bradycardia, tachycardia, recurrent late or prolonged decelerations, or a sinusoidal pattern.
B.Placenta previa: Uterine resting tone usually relaxed. Fetal status at first exam is usually stable. Recurrence of bleeding is common. First bleeding episode in placenta previa is rarely significant. Second or third bleeding episode is often associated with significant vaginal bleeding.
C.Abruptio placentae: Rupture of membranes has bloody show with copious amounts of clear or greenish-brown fluid; the fluid is probably meconium-stained, which signifies fetal distress:
1.Marginal abruption: Uterine resting tone is usually relaxed. Fetal status on the fetal monitor at first exam is usually stable. Labor progresses rapidly with vaginal bleeding or large amounts of bloody show.
2.Moderate abruption: Uterine resting tone is hypertonic. At first exam, the fetus is usually alive. Fetal heart rate (FHR) may exhibit characteristics that are associated with hypoxemia or anemia such as decreased/absent variability, tachycardia, bradycardia, recurrent late or prolonged
decelerations, or a sinusoidal pattern. Labor progresses rapidly with vaginal bleeding or large amounts of bloody show.
3.Severe abruption: Uterine resting tone is hypertonic or board-like.
At first exam, fetus may be dead. If fetus is alive, EFM is consistent with hypoxemia or anemia as listed above.
D.Uterine rupture: Uterine resting tone may be normal or hypertonic. At first exam, fetus may be dead or FHR pattern is consistent with hypoxemia or anemia as previously listed.
Subjective Data
A.Elicit information about onset, duration, and progression of vaginal bleeding. When did it start? Is it continuous bleeding, like a period,
or is it spotting?
B.Ask: How much bleeding has occurred? How many pads have been saturated? What is the size of the blood spots—the size of a quarter or a half dollar?
C.Elicit information regarding the presence or absence of abdominal pain. If present, review the onset, duration, and progression of pain. Is it a continuous discomfort or intermittent cramping? How severe is the pain? Did it have a sudden onset?
D.Is the patient experiencing shoulder pain? This is likely to be referred pain from phrenic nerve irritation caused by intraperitoneal bleeding.
E.Elicit the first day of the patient’s last menstrual cycle, to date pregnancy. Has she had an ultrasound (US) to confirm dating and placental location?
F.Ask the patient if she feels the baby move and if the movement has been normal this day, if more than 18 weeks’ gestation.
Physical Examination
A.Check temperature, pulse, respirations, and blood pressure (BP); peripheral oxygen saturation; urine output; and estimated blood loss. Continuous FHR monitoring is used for patterns suggestive of hypoxemia or anemia:
1.A pregnant patient does not demonstrate signs and symptoms of hypovolemic shock until she has lost 30% of her circulating volume. Tachypnea, tachycardia, hypotension, low oxygen saturation, and air hunger are signs of hypovolemia.
2.Prepare the patient for emergency transport to a hospital even if she is hemodynamically stable.
B.Inspect: Inspect the patient’s general appearance related to discomfort and pain. Observe bleeding characteristics and pooling.
C.Palpate:
1.Check for palpable fetal parts on abdominal wall; note fetal movement.
2.Palpate the uterus for relaxed or hypertonic uterus. Check for contractions. If present, note frequency, duration, and intensity and resting tone to palpation.
D.Auscultate:
1.Auscultate the abdomen; check fetal heart tones, or EFM, for baseline and periodic FHR patterns. Verify FHR versus maternal heart rate.
2.Auscultate the maternal heart and lungs.
E.Perform sterile speculum exam to look for the source of bleeding. Do not perform vaginal bimanual exam until placenta previa is ruled out.
Diagnostic Tests
A.Complete blood count (CBC) and platelets.
B.Prothrombin time (PT), partial thromboplastin time (PTT), and fibrinogen (fibrinogen levels have the best correlation with severity of bleeding).
C.Blood type, Rh status, and type and cross match if indicated.
D.Fetal cell stain, Kleihauer–Betke test, or a flow cytometry test on a specimen of vaginal blood. Fetal cell stain can determine the amount of fetal blood in the maternal circulation.
E.Determine if Rho(D) immune globulin (RhoGAM) is indicated.
F.Ultrasonography/biophysical profile (BPP).
G.Nonstress test (NST)/EFM.
Differential Diagnoses
A.Placenta previa.
B.Abruptio placentae.
C.Uterine rupture or dehiscence.
D.Ruptured vasa previa.
E.Rupture of membranes.
F.Normal bloody show associated with labor.
G.Rectal hemorrhoidal bleeding.
H.Cervical insufficiency.
Plan
A.General interventions:
1.Tocolysis may be considered if the patient has no active hemorrhage and reassuring FHR pattern.
2.If significant vaginal bleeding is present, the primary goal is to maintain oxygen delivery to the mother and fetus while preparing them for transport. Interventions include lateral maternal positioning to avoid vena caval compression; administering supplemental oxygen; initiating large-bore IV line; delivery of fluid bolus of normal saline or lactated Ringer’s solution; keeping flow sheet of vital signs, assessments, actions, and responses; maintaining continuous recording of FHR and uterine activity on EFM; and providing emotional support and anticipatory guidance.
3.If vaginal bleeding is minimal and home management is being considered, discuss risks with the patient and assess her ability to modify her activity to avoid moderate or strenuous exercise, heavy lifting (greater than 20 pounds), or standing for prolonged periods (more than 4 hours). Also assess patient’s access to telephone and transportation in case of major bleeding episode. Consider the distance from the patient’s home to the nearest hospital.
B. 
See Section III: Patient Teaching Guide Vaginal Bleeding: Second and Third Trimesters.
C.Pharmaceutical therapy for preterm placenta previa with preterm contractions:
1.Tocolytics: In patients with contractions, tocolytics may be used while administering a course of betamethasone if bleeding is diminishing or has ceased and delivery is not otherwise mandated by the maternal or fetal condition. Tocolysis may reduce or eliminate uterine contractions, which promote uterine separation and bleeding. Tocolytics should not be used in patients with active vaginal bleeding:
a.Terbutaline sulfate (Brethine) 0.25 mg by subcutaneous injection every 15 minutes times three doses if maternal heart rate less than 120.
b.Indomethacin is not used because of its inhibitory effect on platelet function.
c.The patient may be admitted to an inpatient antepartum unit for parenteral tocolysis such as magnesium sulfate, which has proven beneficial for fetal neuroprotection in patients with preterm (24–32 weeks’ gestation) placenta previa in whom a decision has been made to deliver within 24 hours, but not emergently.
2.Antenatal corticosteroids may be given if preterm delivery is a possibility within the next week and the estimated gestational age (EGA) is less than 34 weeks to enhance fetal pulmonary maturity. Additionally, a course of steroids may be given to women whose first bleed is at 34 0/7 to 36 6/7 weeks’ gestation and who have not received a prior dose:
a.Betamethasone 12 mg may be given by IM injection every 24 hours times two doses.
b.Dexamethasone 6 mg IM may be given every 12 hours times four doses.
c.A single rescue
course of repeat antenatal steroids should be considered in women at less than 34 weeks’ gestation whose prior course was administered at least 7 days previously and who remain at risk of delivering.
3.If the patient is Rh-negative, give her Rho(D) immune globulin (RhoGAM) IM by injection after the initial vaginal bleeding episode. Repeat administration is not necessary if bleeding occurs within 3 weeks of the previous dose. If repeated episodes of bleeding occur, the anti-D antibody can be checked: a low titer suggests that the anti-D level is sufficient to provide ongoing protection against alloimmunization.