How is a blighted ovum (anembryonic pregnancy) typically managed?

Management of Blighted Ovum (Anembryonic Pregnancy)

The management of a blighted ovum (now termed anembryonic pregnancy) should follow a three-pronged approach with expectant, medical, or surgical management options, with the choice based on clinical stability, patient preference, and gestational age. 1

Diagnosis and Terminology

• Anembryonic pregnancy is the current recommended term, defined as a gestational sac measuring ≥25 mm without an embryo, or absence of an embryo on serial examinations obtained at discriminatory time intervals. Terms like "blighted ovum" should be avoided. 2
• Diagnosis is made via transvaginal ultrasound using specific criteria:
  • Diagnostic of Early Pregnancy Loss (EPL): Mean sac diameter ≥25 mm with no embryo 2, 1
  • Additional findings may include a calcified yolk sac or expanded amnion sign, which are poor prognostic indicators 2

Management Options

1. Expectant Management

• Involves waiting for spontaneous passage of pregnancy tissue 1
• Success rates vary depending on gestational age and time from diagnosis
• Requires close follow-up to ensure complete passage of tissue 1
• May take days to weeks for complete resolution 1

2. Medical Management

• Misoprostol is the primary medication used for medical management 1
• Recommended for patients who wish to avoid surgery but desire faster resolution than expectant management 1
• Requires follow-up to confirm complete evacuation of products of conception 1

3. Surgical Management

• Suction dilation and curettage (D&C) is the surgical approach of choice 1
• Indications for surgical management include:
  • Patient preference for immediate resolution 1
  • Hemodynamic instability or significant bleeding 2, 1
  • Signs of infection 2, 1
• Should be performed under ultrasound guidance to reduce risk of uterine perforation 1
• Uterotonic agents should be administered during and after the procedure to reduce bleeding risk 1

Follow-up and Monitoring

• Serial hCG monitoring is recommended until levels return to non-pregnant state 1
• Ultrasound evaluation should confirm complete evacuation of products of conception 1
• Histopathologic examination of tissue is recommended to confirm intrauterine pregnancy and rule out gestational trophoblastic disease 1
• Rho(D) immunoglobulin should be administered to Rh-negative women 1

Complications to Monitor

• Infection risk increases with time after diagnosis, particularly after 18 hours 3
• Hemorrhage is a potential complication, especially with incomplete evacuation 1, 3
• Retained products of conception may require additional intervention 1

Future Pregnancy Considerations

• No minimum waiting period is required before attempting subsequent pregnancy after complete resolution 4
• Advanced maternal age is a risk factor for recurrent anembryonic pregnancy 5

Common Pitfalls to Avoid

• Using outdated terminology like "blighted ovum" or "nonviable pregnancy" which can be hurtful to patients 2
• Failing to confirm complete evacuation of products of conception 1
• Misdiagnosing anembryonic pregnancy when serial examinations are needed for definitive diagnosis 2
• Overlooking the possibility of heterotopic pregnancy (though rare in spontaneous conceptions) 6