Part 1 Of EMC #23 - "Vaginal Bleeding [And Abdominal Pain] In Early Pregnancy" [Differential Diagnosis]

Please also review Part 2 Of EMC #23 – “Vaginal Bleeding [And Abdominal Pain] In Early Pregnancy” [Ectopic Pregnancy]
Posted on April 28, 2020 by Tom Wade MD

Vaginal bleeding and/or abdominal pain in women can be harbinger of ectopic pregnancy which is responsible for 10% of all maternal morality from pregnancy.

Thus either of these complaints in women must be approached with the utmost caution.

Every patient with either of the above complaints requires a serum beta-hCG. The authors state that the urine beta-hCG can be falsely negative. So if available in your practice setting the beta-hCG is preferred.

The Abbott I-Stat point of care system has a cartridge for blood or plasma quantitative or qualitative Beta-hCG. I don’t yet know of the performance characteristics of the test.

Every patient with one of the above complaints AND a positive beta-hCG requires a point of care pelvic ultrasound. If a normal intrauterine pregnancy is not detected (if the scan is indeterminate) the patient requires a transvaginal ultrasound.

In this post I link to and excerpt from the outstanding Emergency Medicine Cases website gives us a thorough review of how to approach these two potentially life-threatening problems in Episode 23: Vaginal Bleeding in Early Pregnancy, [Link is to the podcast and show notes] May 2012, by Drs Dushenski, D, Claybo, and R, Helman, A:

In this episode on Vaginal Bleeding in Early Pregnancy Dr. David Dushenski & Dr. Ross Claybo run through the key clinical pearls of the history, the physical, interpretation of the BhCG and the value of serum progesterone in working up these patients. The newest on point of care ultrasound (POCUS) is discussed in the patient with vaginal bleeding in early pregnancy. The various types of spontaneous abortion including septic abortion are reviewed as well as the management of the unstable patient with massive vaginal hemorrhage. Ectopic pregnancy, in all it’s various presentations is reviewed with particular attention to the most common pitfalls and how to avoid them.

Here is a direct link to the podcast.

And here are excerpts from Differential Diagnosis of Approach To Vaginal Bleeding [And Abdominal Pain] in the show notes:

APPROACH TO VAGINAL BLEEDING IN EARLY PREGNANCY

Differential Diagnosis for vaginal bleeding in early pregnancy

Ectopic pregnancy

Threatened/spontaneous abortion

Anembryonic pregnancy

Non obstetrical causes (vaginal laceration, neoplastic polyps, fibroids)

Gestational trophoblastic disease

History for Vaginal Bleeding in Early Pregnancy

degree and duration of bleeding,

is the pain lateral or central,

history of trauma,

obstetric and fertility history, bleeding disorders, infections,

previous miscarriage history

Anembryonic Pregnancy

Fertilized ovum that does not develop into a normal embryo.

Presents with bleeding in 1st trimester & ultrasound showing a gestational sac without visualization of yolk sac or embryo at appropriate sizes.

Management is similar to a missed abortion (see below) once ectopic is ruled out.

When is βhCG Testing Useful in Vaginal Bleeding

βhCG levels become positive 8-11 days after conception

Levels peak at 10-12 weeks, then gradually decrease.

**Test all women of child-bearing age regardless of history suggesting possibility of pregnancy (1,2).**

Urine βhCG becomes positive 1 week later than serum tests, and may be falsely negative if urine is very dilute

Is there value of serum progesterone in vaginal bleeding in early pregnancy?

[Short answer is no, not in the Emergency Department]

Key βhCG facts to remember

At expected time of missed menses: 2000 IU/mL

IUP visible by transvaginal ultrasound: >1500 IU/mL

IUP visible by abdominal ultrasound: >3000 IU/mL

Cardiac activity visible on ultrasound: >1500 IU/mL by transvaginal, >6500 IU/mL by abdominal

βhCG doubling time = 48-72 hours

Levels become undetectable at 3-4 weeks postpartum

Spontaneous Abortion

Threatened: bleeding with closed cervix and no evidence of fetal demise on ultrasound (U/S)

Risk of complete abortion is 50%, but if fetal heart rate seen (possible at >7 weeks), risk decreases to ~5%

Inevitable:open cervix, products of conception not yet expelled

Almost all progress to complete

Incomplete: products of conception not completely expelled, based on U/S or exam

Compete:All products expelled from uterus, bleeding usually minimal, and os closed

Missed: U/S shows fetal demise, but products remain in uterus, with or without bleeding or symptoms

Septic:rare result of pelvic instrumentation (esp. non sterile conditions), may be mistaken as PID

How should we manage stable patients with abortion?

Management options are expectant management, medical management (misoprostol 800mg inserted vaginally encourages passage of products), and surgical management (D&C).

Update 2018: A randomized trial of 300 women with confirmed first trimester pregnancy loss, showed higher rates of complete expulsion at day 8 with combination mifepristone (200 mg po) and misoprostol (800mcg pv 24 hours later) compared to misoprostol (800 mcg pv) alone, (NNT=6). Abstract

Counseling in the ED must also address psychological concerns:

use sensitivity and empathy,

acknowledge distress and grief,

reassure the patient that neither she nor her partner did anything to cause the miscarriage, and

there is no increased risk for future miscarriages (if < 3 have occurred).

What is the value of the pelvic examination in stable patients with vaginal bleeding in early pregnancy?

If ultrasound findings are available and reassuring, our experts suggest a pelvic exam may be deferred.

However, if high quality ultrasound is not available, or not definitive & reassuring, a pelvic exam is required to assess the uterus and adnexae.

The pelvic exam is also an opportunity for STI screening.

What about unstable patients with abortion and bleeding?

Manage similar to all unstable bleeding patients (resus room, monitors, vascular access, IV fluid +/- unmatched O neg blood, foley).

Investigate for DIC, and urgently consult OB/GYN.

Tranexamic acid (1g IV) +/- oxytocin (40U by IV in 1L NS at 150cc/hour) can be given to slow bleeding before definitive management (in the OR).

**In an unstable patient with massive vaginal bleeding, a pelvic exam is indicated to identify a source and to look for and extract tissue found in the cervix.**