Diagnostic Ultrasound - Abdomen and Pelvis

Retained Products of Conception
Diagnoses: Female Pelvis
TERMINOLOGY
• Retained trophoblastic tissue
• Occurs after delivery or termination of pregnancy
IMAGING
• Grayscale ultrasound
○ Thickened endometrial echo complex or echogenic
intrauterine mass
• Color Doppler ultrasound
○ Presence of vascularity in thickened endometrial echo
complex or mass substantially increases likelihood of
retained products of conception (RPOC)
○ Degree of vascularity may range from hypovascular to
markedly hypervascular compared to normal uterine
myometrium
TOP DIFFERENTIAL DIAGNOSES
• Normal postpartum uterus
• Uterine atony
KEY FACTS
• Intrauterine blood/clot
• Endometritis
• Invasive molar pregnancy
• Arteriovenous malformation (AVM)
• Subinvolution of placental implantation site
• Enhanced myometrial vascularity
PATHOLOGY
• Presence of chorionic villi indicates persistence of placental
tissue
CLINICAL ISSUES
• More frequent following termination and 2nd trimester
deliveries
(Left) Transverse color
Doppler endovaginal US of the
uterus shows a hypoechoic
mass with moderate
internal vascularity, consistent
with retained products of
conception (RPOC). (Right)
Longitudinal color Doppler US
of the uterus in a different
patient shows a thickened
endometrial echo complex ſt
with marked vascularity at
the fundus, consistent with
RPOC. Vascularity in the
endometrium is a helpful clue
to the presence of RPOC.
(Left) Transverse endovaginal
US of the uterus shows a
markedly thickened and
heterogeneous endometrial
echo complex , which was
pathologically proven to
represent RPOC. (Right)
Transverse endovaginal color
Doppler US in the same
patient shows the thickened
endometrial echo complex is
markedly vascular , a
common imaging appearance
of RPOC, which should not be
mistaken for arteriovenous
malformation (AVM)
particularly if there is a focal
endometrial mass.
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