Diagnosis and Management of Threatened Abortion

Indications for Internal Examination

A complete pelvic examination is always indicated in cases of lower abdominal pain to identify the source of pain, which may be caused by pelvic inflammatory disease, ovarian mass or torsion, and/or normal or ectopic pregnancy, as recommended by the American Academy of Pediatrics 1
Persistent symptomatic vaginal discharge warrants a speculum examination, though vaginal swabs can be obtained by either the provider or patient without full pelvic exam, according to the American Academy of Pediatrics 1
Evaluation of lower abdominal pain requires examination to differentiate between threatened abortion and other causes such as ectopic pregnancy, ovarian torsion, or pelvic inflammatory disease, as stated by the American Academy of Pediatrics 1
A speculum or bimanual examination is now considered unnecessary before prescribing most forms of contraception, as there is nothing that would be found on pelvic examination that would be a contraindication to prescribing hormonal contraception, as recommended by the American Academy of Pediatrics 1

Pelvic examinations are not needed routinely to provide contraception safely to a healthy client, unless inserting an intrauterine device (IUD) or fitting a diaphragm, as stated by the Centers for Disease Control and Prevention 2

Do not delay ultrasound imaging based on β-hCG levels below a discriminatory threshold, as ectopic pregnancies can present at almost any β-hCG level, and rupture has been documented at very low levels, as recommended by the American College of Emergency Physicians 3, 4

Administer 50 μg of anti-D immunoglobulin to Rh-negative women in all cases of documented first-trimester loss of established pregnancy to prevent Rh-D alloimmunization, as recommended by the American College of Emergency Physicians 5, 6
Fetomaternal hemorrhage occurs in 48% of threatened abortion cases, with an overall rate of 32% in patients undergoing spontaneous abortion, as reported by the American College of Emergency Physicians 5, 6
The American College of Obstetricians and Gynecologists states there is no evidence-based recommendation for anti-D immunoglobulin administration in threatened abortion with a viable fetus, and many physicians do not treat when there is a live embryo or fetus, as stated by the American College of Obstetricians and Gynecologists 6

Transvaginal ultrasonography is the diagnostic method of choice to confirm fetal viability and detect the presence of subchorionic hematoma, according to the American College of Emergency Physicians 7
The diagnostic method of choice should also rule out other complications such as ectopic pregnancy, as recommended by the American College of Emergency Physicians 8

The American College of Obstetricians and Gynecologists states that there is no evidence-based recommendation for anti-D immunoglobulin administration in threatened abortion with a viable fetus, and many physicians do not treat when there is a live embryo or fetus 9
Administer 50 μg of anti-D immunoglobulin to Rh-negative women in all cases of documented first-trimester loss of established pregnancy, as recommended by the American College of Emergency Physicians 9, 10

Serial ultrasound examinations should be performed to assess fetal growth and development, as recommended by the American College of Obstetricians and Gynecologists 7

The American College of Obstetricians and Gynecologists states that administration of 50 μg anti-D immunoglobulin is reasonable in threatened abortion with a viable fetus, particularly if bleeding is more than spotting, due to the 11% incidence of fetomaternal hemorrhage and the catastrophic consequences of Rh alloimmunization 11
Administer 50 μg of anti-D immunoglobulin to all Rh-negative women with documented first-trimester pregnancy loss, as fetomaternal hemorrhage occurs in 32-48% of threatened abortion cases 11

When transvaginal ultrasound findings are indeterminate, serial quantitative β‑hCG measurements should be obtained; a viable pregnancy is expected to show an appropriate rise in β‑hCG levels. [12][13]

If the initial ultrasound is nondiagnostic, a repeat β‑hCG measurement at 48 hours is recommended; an increase of ≥ 53 % over this interval supports ongoing viability. [12][13]

Hemodynamic instability (e.g., hypotension or tachycardia) in a patient with threatened abortion mandates urgent surgical evaluation. 13
Detection of cervical dilation on pelvic examination signifies progression to inevitable abortion and calls for prompt definitive management. 13