Sonographic Imaging of the
Female Patient with Pelvic
Pain/ Bleeding
Sarah A. Stahmer MD
Cooper Hospital/University
Medical Center
Case Presentation

24 yo female presents with missed period,
cramping, midline abdominal pain and
spotting
 VS: BP 120/80
HR 110
 Pelvic:
– Cervical os is closed with minimal bleeding
– No CMT, adenexa symmetric

Urine hCG is +
Case presentation





A bedside ultrasound
is performed
The US reveals an IUP
The patient is
discharged to home
with threatened
abortion precautions
LOS = 30 minutes
Applies to 60% of pts
Role of Bedside Sonography

Identify an IUP

Establish fetal viability
Secondary Indications

Hemodynamic instability in a female pt

Trauma and pregnancy

Localization of IUD/foreign body

Identify sources of pelvic pain in nonpregnant patients
Imaging: Transabdominal
Uses a lower frequency transducer: 3.5 –5 mHz
 Better penetration, larger field of view
 It should be the initial imaging window to assess
for

– Advanced IUP
– Fibroids/masses
– Pelvic fluid

The bladder should be full to provide an acoustic
window
Endovaginal

Uses a higher frequency transducer: 6.0-7.5mHz
 Provides optimal imaging of:
– Endometrium
– Myometrium
– Cul-de-sac
– Ovaries

A full bladder is not necessary for this approach
 Is usually better tolerated by patients
Scanning Protocol: Transabdominal

Image the patient before obtaining a urine
sample

Can fill the bladder via foley and instill 300
cc NS but…

If the bladder is empty, go directly to TV
imaging after the pelvic exam
Probe
Selection
“Workhorse”probe
 3.5 to 5.0 MHz
 Multi-frequency probe
 Good for most
cardiac/abdominal
applications

Uterus

An oval organ located
superior to the full bladder
 The maximum size of the
non-gravid uterus is 5-7
cm x 4-5 cm

The endometrial stripe is
the opposed surfaces of
the endometrial cavity
Transabdominal / Transverse view
Right
Left
Cul-de-sac

Located posterior to the
uterus and upper vagina

A small amount of fluid
may be seen in mid cycle

A small amount of fluid in
the posterior cul-de-sac
may be the only
sonographic finding in EP
Bladder
uterus
Probe Selection

Endovaginal Probe
 5 to 8 mHz variable
frequency probe
 Up to 180 degree angle
of view
Endovaginal Examination

Best performed immediately following the pelvic
exam
 An empty bladder is required for an optimal
endovaginal (EV) exam
 A full bladder:
– Displaces the anatomy beyond the focal length of the
transducer
– Will create artifacts that will compromise imaging
Before Performing a TV Exam:

Explain that the EV exam is better for
seeing ovaries and early pregnancy
 Show the patient the probe
 Allow her the option of inserting it herself
 Inform her that it is usually more
comfortable than the TA exam which
requires a full bladder

The transducer probe should be covered with a
coupling gel followed by a protective probe
cover

Non-medicated/ non-lubricated condoms are
recommended as a probe cover

Patients with latex allergies will require an
alternative barrier

Air bubbles within the sheath may increase
artifacts and compromise imaging
Longitudinal view
Coronal view
The Uterus

Early in the menstrual cycle
– endometrium measures 4-8mm

Secretory phase
– endometrium measures 7-14 mm

Post-menopausal patient
– endometrial stripe usually less than 9 mm
Endometrial Stripe (ES)
Measurements

In the post-partum patient, a thickened ES is
suggestive of retained products of conception

In the pregnant patient, an ES measurement of < 8
mm in the absence of an IUP is suggestive of EP

Thickening of the endometrial stripe in the postmenopausal patient with vaginal bleeding should
raise suspicions for endometrial carcinoma
Ovaries

Lie posterior/lateral to the
uterus

Anterior to the internal
iliac vessels and medial to
the external iliac vessels

Identified by a ring of
follicles in the periphery
Ovaries

After ovulation a corpus luteal cyst may be
present
– Observed in approximately 50% of ovulating
females
– Should not be seen beyond 72 hours into the
next cycle
 Small amount of fluid in the rectouterine pouch
may be seen during ovulation
Ovarian Cysts

Follicular cyst (2.5 –10 cm)
– Thin, round, unilocular

Functional corpus luteum cyst
– Normal up to 16 weeks GA
– Appears as a unilateral, unilocular 5-11 cm cyst
– Appearance can be highly variable
– Hemorrhage inside the cyst not uncommon
Assessment of the Pregnant Patient

Identify gestational sac

Demonstrate a myometrial mantle in the
transverse view

Identify yolk sac and/or fetal pole

Note if there is fluid in the cul-de-sac
Gestational Sac

Anechoic area within the uterus surrounded
by two bright echogenic rings
– Decidua vera (the outer ring)
– Decidua capsularis (the inner ring)

This is referred to as the double decidual
sac sign (DDSS)
Yolk Sac

First embryonic structure that can be
detected sonographically
 Visualized approximately 5-6 weeks after
the last menstrual period
 Bright, ring like structure within the GS
 Should be readily seen when the GS sac is
greater than 10 mm (using EVS)
Fetal Pole

Can be first seen on EV when the fetus is
approximately 2 mm in size
 A thickened area adjacent to the yolk sac
 The CRL is the most accurate sonographic
measurement that can be obtained during
pregnancy
A Fetal Heart Beat

An important prognostic indicator

The rate of spontaneous abortion is
extremely low (2- 4%) after the detection of
normal embryonic cardiac activity

The normal fetal heart rate in early
pregnancy is 112-136
Definite IUP

A gestational sac
with a sonolucent
center (greater than
5 mm diameter)
 Surrounded by a
thick, concentric,
echogenic ring
 GS contains a fetal
pole or yolk sac, or
both
Abnormal IUP

A GS larger than 10-13 mm diameter(TV)
or 20mm (TA) without a yolk sac

A GS larger than 18 mm (TV) or 25mm
(TA) without a fetal pole

A definite fetal pole without cardiac activity
after 7 wks GA
Empty gestational sac
Fetal demise
Sonographic Spectrum of EP

Ruptured ectopic pregnancy

Definite ectopic pregnancy

Extrauterine empty gestational sac

Adenexal mass

Pseudogestational sac

Empty uterus
Definite Ectopic Pregnancy
A thick, brightly echogenic, ring-like
structure located outside the uterus with a
gestational sac containing an obvious fetal
pole, yolk sac or both.
Ruptured Ectopic Pregnancy
Free fluid or blood in the cul-de-sac or the
intra-peritoneal gutters (hemoperitoneum)
This finding and a positive pregnancy test
essentially makes the diagnosis!
clot
Clot/fluid
Extrauterine Gestational Sac

Extra-uterine mass
containing a thick,
brightly echogenic
ring surrounding an
anechoic area
 Brightly echogenic
appearance may be
helpful
 Tubal ring
Adenexal Mass
Pseudogestational Sac

Stimulation of the endometrium
 Decidual breakdown results in a central
anechoic area
 Can be confused with “early IUP”
 Does not have double decidual sac sign
 Correlation with ß hCG helpful
Pseudogestational sac
Ectopic
Interstitial Ectopic Pregnancy

Implantation near the insertion of the
fallopian tubes
 Highly vascular area
 Suspect when GS is not centrally located
 Demonstration of endometrial mantle is
critical to the diagnosis
Empty Uterus

Correlation with ßhCG
critical

ßhCG >discriminatory
zone and empty uterus
is EP until proven
otherwise
Discriminatory HCG Zone

5 weeks since last normal
LMP
– ß hCG value = 1800 mIU


TAS landmarks
– 5 to 8-mm GS
TVS landmarks
– 5 to 8-mm GS
– With or w/o yolk sac
Discriminatory HCG Zone

6 weeks since last
normal LMP
– ß hCG = 7200

TAS landmarks
– Yolk sac
 TVS landmarks
– Yolk sac and
embryo
– Possibly FHM
Discriminatory HCG Zone

7 weeks since last
normal LMP
– ß hCG = 21,000

TAS landmarks
– 5 to 10-mm embryo
with FHM
 TVS landmarks
– 5 to 10 mm embryo
with FHM
Rule - in IUP Protocol
Clinically stable females with:
(1) Lower abdominal pain
(2) Vaginal bleeding
(3) Orthostasis
(4) Or risk factors for EP
Positive urine preg
Ultrasound
Rule - in IUP Protocol
Ultrasound
Definite IUP
Definite EP
Can DC to home
with f/u
OB consultation
Rule - in IUP Protocol
Ultrasound
No IUP but…
+ Adenexal tenderness or CMT
Free fluid in the cul de sac
And/or hCG > discriminatory zone
OB
Consultation
Rule - in IUP Protocol
Ultrasound
No IUP
Benign exam
ßhCG > discriminatory zone
DC to home
F/u exam and
ßhCG w/in 48 hrs
Rule-In IUP Protocol

Sixty percent of patients will have IUP
– “Rules out” ectopic pregnancy by “ruling
in” IUP
 What about heterotopic pregnancy?
– Increased in patients undergoing
ovulation induction
consult OB
– Risk is 1/30,000 in non-induced pregancy
Pitfalls

Diagnosing intrauterine fluid collections as
“early” IUP
 Low hCG does not mean “low risk” for EP
 Failure to determine the exact location of a
gestational sac
 Cul-de-sac fluid may be the only sonographic
finding of extrauterine pregnancy