Third trimester hemorrhage

 

Laima Maleckienė

 

Etiology

Obstetric causes:

·        “bloody show”

·        placenta previa

·        placenta abrubtion

Nonobstetric causes: cervicitis, cervical polyps, cancer; vaginal varices.

Placenta previa

In case of placenta previa - placenta situated in lower uterine segment covering totally or partially the internal cervical os. The incidence of placenta previa is about 0.5% at term.

Risk factors:

·        multiparity

·        prior cesarean section

·        large placenta (e.g. multiple gestation)

Classification:

Total placenta previa - the internal os is covered completely 

Partial placenta previa - the internal os is covered partially .

Marginal placenta previa - the edge of the placenta is at the margin of the internal os.

Diagnosis

Symptoms and signs:

·        sudden, painless and profuse vaginal bleeding

·        uterus usually is soft and nontender

·        fetal malpresentation,

·        no fetal disstress.

Ultrasonography is a necessity for diagnosis.

Management

Hospitalization

The type of treatment depends on:

·        amount of uterine bleeding

·        gestational age and viability of the fetus

Expectant therapy (preterm fetus, no severe bleeding):

·        Bed rest.

·        Tocolysis.

·        Steroids for fetal lung maturation.

Delivery

Cesarean section is the accepted method of delivery in practically all cases of placenta previa Cesarean delivery should be performed as soon as lung maturity is documented, or when hemorrhage is so severe as to mandate delivery despite fetal immaturity.

Placental abruption

Placental abruption is defined as the separation of a normally implanted placenta from the uterine site before the delivery of the fetus. Placental abruption occurs in 0,5-1,8% of all pregnancies. About 50% of cases occur before the onset of labor.

Predisposing factors:

Classification

Grade I (mild). The diagnosis of abruptio placentae is made retrospectively on postpartum detection of a small retroplacental clot.

Grade II (intermediate). This diagnosis is based on the classic features of abruptio placentae with uterine hypertonicity, but the fetus is still alive.

Grade III (severe). The fetus is dead (separation of 50% or more of the placental area usually is incompatible with fetal life):

Grade IIIA. Overt coagulopathy is not present.

Grade IIIB. Overt coagulopathy results.

Placental abruption may be:

·        total

·        partial

Diagnosis

Signs and symptoms:

·        external (in about 80% of patients) or concealed hemorrhage,

·        sudden severe abdominal (uterine) or back pain,

·        uterine tenderness,

·        persistent uterine hypertonus,

·        evidence of fetal distress,

·        hypovolemic shock,

·        coagulation defects.

Patients with a mild placental abruption may be asymptomatic.

Management

Urgent hospitalization

Delivery

Cesarean section is indicated for:

·        fetal distress,

·        heavy bleeding.

Vaginal delivery is indicated:

·        if  no fetal distress,

·        when the fetus is dead and absence of life-threatening bleeding.

Fluid and blood replacement therapy

Correction of the coagulopathy

Expectant therapy – if the fetus is immature, bleeding is small, no fetal distress, and uterine irritability is absent:

·        tocolytics (contraversial opinion),

·        steroids for fetal lung maturation.

References

 

  1. Cunningham FG, Macdonald PC, Gant NF, Leveno KJ, III Gilstrap LC, Hankins GD, et al. Williams obstetrics. 20th ed. New York: Appleton & Lange; 1997. p.389-415.
  2. Saleh HJ, Haney EI. Placenta previa and accreta. In: Sciarra JJ, editor. Gynecology and obstetrics. Philadelphia: Lippincott Williams & Wilkins; 2001. Vol 2; Chap 49. p. 1-11.
  3. Baron F, Hill WC. Placenta previa, placental abruptio. Clin Obstet Gynecol 1998;41:527-32.
  4. Yeo L, Ananth CV, Vintzileos AM. Placental abruption. In: Sciarra JJ, editor. Gynecology and obstetrics. Philadelphia: Lippincott Williams & Wilkins; 2001. Vol 2; Chap 50. p. 1-25.