Management of Blighted Ovum (Anembryonic Pregnancy)
The term "blighted ovum" is outdated and should be replaced with "anembryonic pregnancy," which requires active management rather than expectant observation, with three evidence-based options: expectant, medical, or surgical evacuation, chosen based on patient preference, clinical stability, and gestational age. 1, 2
Correct Terminology and Diagnosis
Avoid using "blighted ovum" – the American College of Obstetricians and Gynecologists recommends the term "anembryonic pregnancy" or "early pregnancy loss (EPL)" instead, as outdated terminology can be hurtful to patients. 1, 2
Diagnostic criteria via transvaginal ultrasound include a mean gestational sac diameter ≥25 mm without an embryo, or absence of an embryo ≥14 days after initial visualization of the gestational sac. 1, 2
Confirm the diagnosis with serial examinations obtained at discriminatory time intervals to avoid misdiagnosis, as premature intervention can occur if criteria are not strictly followed. 2
Management Options: A Structured Approach
1. Expectant Management (Wait for Spontaneous Passage)
Success rates are modest: Only 53% of anembryonic pregnancies resolve spontaneously within 2 weeks, compared to 71% for incomplete miscarriage. 3
This approach carries significantly higher maternal morbidity (60.2% vs 33.0% with active abortion care), with intraamniotic infection occurring in 38.0% of expectant cases versus 13.0% with active management. 1
Absolute contraindications to expectant management include hemodynamic instability, profuse bleeding, signs of infection (maternal tachycardia, purulent cervical discharge, uterine tenderness), or patient preference for faster resolution. 1, 2
If choosing expectant management, limit observation to 2 weeks maximum with weekly ultrasound monitoring, as waiting longer does not improve success rates and increases infection risk. 3
2. Medical Management (Preferred First-Line for Most Cases)
Mifepristone 200 mg orally followed by misoprostol 800 mcg vaginally/buccally is more effective than misoprostol alone, particularly for anembryonic pregnancy, with success rates of 66.7% and better tolerability than higher mifepristone doses. 1, 4
Misoprostol 800 mcg vaginally alone achieves high success rates and is the preferred first-line option when mifepristone is unavailable. 1
Expected side effects include heavy bleeding in 38.3% of patients (stopping by day 7 on average), median pain scores of 4.5/10, with 25% requiring intramuscular opiates, and nausea (7%) or diarrhea (7%). 4
This option is suitable for outpatient or home-based care before 9 weeks gestation, offering significant advantages in cost and convenience. 1
3. Surgical Management (Suction D&C)
Immediate surgical evacuation is mandatory for patients with hemodynamic instability, significant bleeding, or signs of infection. 1, 2
Vacuum aspiration is the procedure of choice, associated with less blood loss and pain compared to sharp curettage. 1
Surgical management has lower complication rates compared to medical management: hemorrhage (9.1% vs 28.3%), infection (1.3% vs 23.9%), and retained tissue requiring additional procedures (1.3% vs 17.4%). 1
However, surgical evacuation may be more psychologically traumatic for some patients, making shared decision-making essential. 1
Critical Post-Management Steps
All Rh-negative women must receive anti-D immunoglobulin (50 mcg dose) to prevent alloimmunization, as fetomaternal hemorrhage occurs in 32% of spontaneous abortions. 1
Serial hCG monitoring until levels return to non-pregnant state and ultrasound evaluation to confirm complete evacuation are essential. 2
Histopathologic examination of tissue should be performed to confirm intrauterine pregnancy and rule out gestational trophoblastic disease. 2
Immediate contraceptive counseling is crucial, as ovulation can resume within 2-4 weeks post-abortion; combined hormonal contraceptives or implants can be initiated immediately without waiting for next menses. 1
Common Pitfalls to Avoid
Never delay treatment waiting for fever if infection is suspected – clinical signs like maternal tachycardia, purulent discharge, or uterine tenderness warrant immediate broad-spectrum antibiotics and urgent evacuation. 1
Do not pursue expectant management in the presence of bleeding – this is an absolute contraindication due to increased risk of hemorrhage and infection. 1
Beware of misdiagnosis – careful ultrasound evaluation is essential to differentiate anembryonic pregnancy from ectopic pregnancy, as heterotopic pregnancy (though rare) can occur. 1, 5
Avoid aggressive or repeated curettage to prevent long-term complications like Asherman syndrome (intrauterine adhesions). 1