Threatened miscarriage vs Inevitable miscarriage
How to tell Threatened miscarriage and Inevitable miscarriage apart when a board question makes them look alike.
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Cervical os status on pelvic exam.
Side by side
First-trimester bleeding with a closed cervical os and viable intrauterine pregnancy indicates threatened miscarriage.
Vaginal bleeding with cramping and an open cervical os before fetal viability indicates inevitable miscarriage.
Bleeding occurs while pregnancy tissue remains retained and cervical integrity is preserved.
Cervical dilation reflects ongoing expulsion process that cannot be halted.
Transvaginal ultrasound shows live intrauterine embryo with cardiac activity; serial beta-hCG generally rises appropriately for gestational age.
Open cervical os with intrauterine products and declining or plateauing beta-hCG supports inevitable loss trajectory.
The trap
Assuming all early bleeding is threatened miscarriage can miss inevitable loss. An open os changes counseling and management toward expectant, medical, or uterine evacuation planning.
The repair move
Next best step: confirm hemodynamic stability and Rh status, perform transvaginal ultrasound and pelvic exam, give Rho(D) immune globulin to unsensitized Rh-negative patients, then manage threatened loss expectantly or treat inevitable loss with misoprostol or uterine aspiration as indicated.
Try a free question
CoreA 26-year-old woman at 9 weeks has light bleeding and no tissue passage. Pelvic exam shows closed cervical os, and transvaginal ultrasound shows a live embryo. What is the most likely diagnosis?
Show answer and explanation
Answer: A. Threatened miscarriage. Closed os plus viable intrauterine pregnancy defines threatened miscarriage.
Why the other choices are tempting
- B. Incorrect because inevitable miscarriage requires an open cervical os.
- C. Incorrect because incomplete miscarriage typically has partial tissue expulsion and retained products.
- D. Incorrect because ectopic pregnancy lacks a viable intrauterine embryo in most cases.
- E. Incorrect because molar pregnancy has abnormal trophoblastic findings, not a normal viable embryo.
Flashcards
Tap a card to flip it.
What pelvic exam finding separates threatened from inevitable miscarriage?
A closed os suggests threatened miscarriage, while an open os indicates inevitable miscarriage.
What ultrasound finding supports threatened miscarriage?
A viable intrauterine pregnancy with fetal cardiac activity.
Quick answers
What is the fastest way to tell Threatened miscarriage from Inevitable miscarriage?
Cervical os status on pelvic exam.
What is the key clue for Threatened miscarriage?
First-trimester bleeding with a closed cervical os and viable intrauterine pregnancy indicates threatened miscarriage.
What is the key clue for Inevitable miscarriage?
Vaginal bleeding with cramping and an open cervical os before fetal viability indicates inevitable miscarriage.
What is the common trap with Threatened miscarriage vs Inevitable miscarriage?
Assuming all early bleeding is threatened miscarriage can miss inevitable loss. An open os changes counseling and management toward expectant, medical, or uterine evacuation planning.