Early pregnancy loss, often referred to as miscarriage or spontaneous abortion, includes all intrauterine non-viable pregnancies in the first trimester. EPL is common, occurring among 10-20% of clinically recognized pregnancies (ACOG 2015, Prine 2011, Blohm 2008 ). Nearly half of all EPLs are the result of random genetic errors (and the most common risk factors are advanced maternal age and prior early pregnancy loss) while other factors such as environment, exposures, and immunologic factors are also implicated (ACOG 2015, Prine 2011 ).  Most of the time with individual patients, it’s not possible to determine the cause of the pregnancy loss.

Patients with EPL often present with vaginal bleeding and/or abdominal cramping. Alternatively, a non-viable pregnancy can be an incidental finding detected by ultrasound or absence of fetal heart tones at a follow up appointment. EPL can be classified based on ultrasound findings or clinical exam, as outlined in the table below.

Terminology Clinical definition Ultrasound findings
Missed Abortion A non-viable intrauterine pregnancy, either anembryonicor an embryonic demise, often discovered by ultrasound. The patient may be asymptomatic or have a history of bleeding. The cervix is closed. Anembryonic gestation or embryonic demise (see below)
Anembryonic Gestation Growth of a gestational sac without an associated embryo or yolk sac.  Formerly called “blighted ovum” Enlarged gestational sac without embryo (See criteria in Chapter 3)
Embryonic or Fetal Demise Loss of viability of a developing embryo or fetus Embryonic or fetal pole with no cardiac activity ≥7mm (see criteria in Chapter 3 )
Threatened Abortion The cervix is closed with uterine bleeding but without passage of gestational tissue. Pregnancy viable at time of presentation and patient may or may not miscarry. Findings appropriate for stage of pregnancy, may or may not show subchorionic hemorrhage
Inevitable Abortion The cervix is dilated with bleeding and uterine cramping, and passage of tissue is expected. Findings may be appropriate for stage of pregnancy, with or without fetal cardiac activity.
Incomplete Abortion The cervix is dilated and some, but not all, of the pregnancy tissue is expelled. Heterogeneous or echogenic material, usually in the lower uterine cavity or in cervical canal
Complete Abortion The pregnancy tissue has expelled completely No pregnancy (sac/embryo or fetus) in intrauterine cavity, with possible endometrial thickening

Adapted from Prine 2011.

In the past, EPL was primarily managed in the operating room with dilation and curettage. Now management of EPL commonly occurs in the outpatient setting, which is recognized as being safe, efficient, and cost-effective, while also providing more choices for patients. While some Emergency Departments (EDs) have worked to build capability to manage EPL, the goal of most has been to evaluate for possible ectopic pregnancy, manage patients with hemodynamic instability, and defer management of stable definitive or potential EPL to the outpatient setting (ACEP 2012). Patients and providers in Catholic institutions may face additional barriers to managing EPL, particularly for inevitable abortion where there is still an embryonic or fetal heartbeat (Freedman 2008 ).


EARLY ABORTION TRAINING CURRICULUM Copyright © 2020 by UCSF Bixby Center for Global Reproductive Health. All Rights Reserved.