In most cases of early pregnancy loss, expectant management, medical management, and surgical management provide similarly safe and effective treatment options; however, of the three options, surgical management had the highest rates of guaranteed success and fastest recovery times, according to Sarah Prager, MD, of the University of Washington, and colleagues from the Committee on Practice Bulletins at theAmerican Congress of Obstetricians and Gynecologists (ACOG).
The guidelines incorporated research suggesting new, stricter cutpoints for crown-rump length and mean gestational sac measurements in ultrasound diagnostics more accurately predict early pregnancy loss.
Early pregnancy loss, defined as an empty gestational sac or a lack of fetal heart beat prior to reaching the 13th week of gestation, ends roughly 10% of all pregnancies. This time frame, known as the first trimester, is the high-risk period of pregnancy, as approximately 80% of all miscarriages occur in this stage.
Who’s at Risk?
According to ACOG, the most common risk factors for early pregnancy loss include the incidence of a previous miscarriage and advanced maternal age. Fetal chromosomal abnormalities contributed to close to half of all early pregnancy losses.
Broken down by age groups, women ages 20 to 30 experience early pregnancy losses at a rate of 9%-17%. From ages 35-39, that rate increases to 20%, and then doubles to 40% once women reach 40. By 45 years of age, early pregnancy loss effects 80% of all pregnancies.
To differentiate between symptoms that are similar in normal gestation, ectopic pregnancy, molar pregnancy, and early pregnancy loss, such as vaginal bleeding and uterine cramping, ACOG recommended the following:
- Take a detailed medical history
- Conduct a thorough physical exam
- Perform an ultrasound
- Test the patient’s beta-hCG serum
Although, in straightforward cases, where the ultrasound provides a definitive diagnosis of an empty uterus, beta-hCG serum testing might not be necessary. For example, if a patient with a ultrasound-confirmed intrauterine pregnancy presents with severe vaginal bleeding, a second ultrasound might be the only testing needed to confirm the loss.
However, the diagnostic criteria for detecting early pregnancy loss through an ultrasound changed a few years ago.
The old diagnostic threshold required a crown-rump length of 5 mm without cardiac activity or an empty gestational sac measuring 16 mm in average diameter to confirm early pregnancy loss.
Based on two 2011 studies, these cutoffs have been adjusted.
In a study by Abdallah et al. with 1,060 women, the 5 mm crown-rump length cutpoint resulted in an early pregnancy loss false-positive rate of 8.3%. The cutpoint had to be changed to 5.3 mm to achieve a 0% false-positive rate.
In the same study, the 16 mm gestational sac measurement was associated with a 4.4% false-positive rate for early pregnancy loss. The mean diameter cutoff for a gestational sac without an embryo had to be lengthened to 21 mm to reach a 0% false-positive rate.
In a follow-up study, which included 359 women from the first study, the authors found that the average gestational sac diameter and the crown-rump length did not accurately predict fetal viability. Instead, they concluded that the gestational sac had to be empty on the first scan, and remain so on a second scan performed 7 days or more after the initial scan.
The Society of Radiologists used these studies for their 2013 criteria for early pregnancy loss diagnosis; however, their cutpoints were quite a bit stricter than those in the ACOG guidelines.
In cases of suspicion of ectopic pregnancy, conduct an ultrasound and a beta-hCG serum test.
In addition, potential signs suggesting an early pregnancy loss, which should be re-evaluated 7 to 10 days after onset, include slow fetal heart rate (less than 100 beats per minute at 5 to 7 weeks) and subchronic hemorrhage.
Treatment options for early pregnancy loss include expectant management, medical treatment, and surgical evacuation. And, even though there “is no evidence that any approach results in different long-term outcomes,” specific circumstances might determine which treatment path would best serve the patient.
Expectant managment successfully evacuates the fetus in roughly 80% of cases, but this sit-and-wait method can take up to 8 weeks to complete and works best in women who actually show symptoms of early pregnancy loss.
ACOG suggested this option should only be used during the first trimester, and to provide the patient with pain medication and extensive education on the process, including the knowledge that if they go through two maxipads per hour for 2 hours in a row, they need to seek medical attention.
Medical management, treatment with misoprostol, can be used in women who don’t have signs of infection, severe anemia, bleeding disorders, or hemorrhage. Misoprostol reduces the risk of surgical evacuation by 60% and completes the early pregnancy loss faster than expectant management.
Within 7 to 10 days, misoprostol showed success rates of 80% to 81% compared with 52% to 85% for expectant management.
ACOG recommended an initial dose of 800 mcg vaginally and a second dose, if needed, sometime after 3 hours but sooner than 7 days after the initial dose. Also, the patient should receive sufficient pain medication.
Within 7 to 14 days of taking the misoprostol, a follow-up ultrasound, or a beta-hCG serum test where there’s no access to ultrasound, should be used, along with the patient’s report on the passage of tissue, to determine successful evacuation.
In the event that the misoprostol fails, expectant management, or surgical evacuation are appropriate.
Surgical management is the fastest option, has a near 99% success rate, and provides a better choice for women with infections, comorbidities, and cardiovascular disease.
ACOG recommended suction curettage over sharp curettage, as electric vacuum source or manual vacuum aspirators can be used in an office setting and therefore require less sedation and use of expensive resources.
Rates of pelvic infection, hemoglobin levels greater than or equal to 3 g/dL, and rates of hospitalization with and without transfusion, were similar enough between treatment groups that ACOG reviewers concluded “that patient preference should guide choice of intervention.”
The reviewers found no evidence to support the need to delay intercourse or conception after early pregnancy loss.
If the patient is Rh(D) negative and unsensitized, administer 50 mcg Rh(D)-immune globulin within 72 hours of the first dose of misoprostol, planned expectant management, or after surgical management of early pregnancy loss. The 300 mcg dose, which might be easier to find, is also acceptable.
For the most part, medical literature does not support pelvic rest, vitamins, uterine relaxants, progesterone, or beta-hCG to prevent early pregnancy loss, except for anticoagulants, aspirin, or both, in women with antiphospholipid syndrome.