From the Guidelines
Miscarriage and spontaneous abortion are medically the same condition, referring to the natural loss of a pregnancy before 20 weeks gestation, and their management approach is based on the clinical presentation and patient preference, as outlined in the recent consensus conference recommendations by the Society of Radiologists in Ultrasound 1. The management of miscarriage versus spontaneous abortion depends on the clinical presentation, which can be categorized into five main categories of early pregnancy loss (EPL): concerning for, diagnostic of, in progress, incomplete, and completed, as defined by the Society of Radiologists in Ultrasound lexicon 1.
- Concerning for EPL is defined by specific criteria on transvaginal ultrasound (TVUS), including embryonic crown-rump length (CRL) <7 mm and no cardiac activity, mean sac diameter (MSD) 16-24 mm and no embryo, or absence of embryo with cardiac activity 7-13 days following visualized gestational sac (GS) and no yolk sac (YS) 1.
- Diagnostic of EPL is defined by more definitive criteria, including CRL ≥7 mm and no cardiac activity, MSD ≥25 mm and no embryo, or absence of embryo with cardiac activity ≥14 days after visualization of GS and no YS 1. For confirmed pregnancy loss, three options exist: expectant management, medical management, or surgical management.
- Expectant management involves waiting for natural passage of tissue, which succeeds in 80% of cases within 2-4 weeks but carries risk of incomplete evacuation.
- Medical management uses misoprostol, which is 80-90% effective for pregnancies under 9 weeks.
- Surgical management via vacuum aspiration or dilation and curettage provides immediate resolution with 95-100% effectiveness but carries surgical risks. All patients should receive Rh immunoglobulin (RhoGAM) if Rh-negative, pain management with NSAIDs or acetaminophen with opioids if needed, and counseling about when to seek emergency care for heavy bleeding, as recommended by recent guidelines 1. Follow-up should include monitoring for complete evacuation, emotional support, and discussion about contraception and future pregnancy planning. It is essential to note that enhanced myometrial vascularity (EMV) is a common finding that can be confused with other rare entities, such as arteriovenous fistula and arteriovenous malformation, which may lead to unnecessary work-up, and should be recognized and managed accordingly 1.
From the Research
Management Approach for Miscarriage versus Spontaneous Abortion
The management approach for miscarriage and spontaneous abortion can be similar, with a focus on medical and surgical options.
- Medical management using mifepristone and misoprostol is a safe and effective option for early pregnancy loss or miscarriage, as well as for abortion 2.
- Expectant treatment and dilatation and curettage are also options for managing first-trimester incomplete spontaneous abortion, with patient preferences playing a significant role in the decision-making process 3.
- Misoprostol can be used for outpatient management of missed miscarriage, with high success rates and low complication rates 4, 5.
- Ultrasonography and beta-hCG testing can be used to verify the effectiveness of medical abortion, with beta-hCG being as effective as ultrasound in confirming a successful medically induced abortion 6.
Medical Management
Medical management using mifepristone and misoprostol is a common approach for miscarriage and spontaneous abortion.
- This approach can be used in ambulatory settings without special equipment or on-site emergency services 2.
- Misoprostol can be administered sublingually, with a high rate of success in avoiding curettage and a low rate of complications 5.
Patient Preferences
Patient preferences play a significant role in the management of miscarriage and spontaneous abortion.