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Radiol Clin N Am 42 (2004) 315 – 327

The role of ultrasound in pregnancy-related emergencies
Noam Lazebnik, MD*, Roee S. Lazebnik, PhD
Department of Obstetrics and Gynecology, MacDonald Women’s Hospital, University Hospitals of Cleveland,
Case Western Reserve University School of Medicine, 11100 Euclid Avenue, Cleveland, OH 44106, USA

Although most births are uneventful, about 15%
ofall birthing women experience potentially lifethreatening complications, and at least 1% to 2%
require major surgery. Although some complications
can be prevented, and some predicted preemptively,
most of the severe complications cannot be anticipated. To reduce mortality, a key component of maternal health care is the ability to diagnose, confirm,
and treat women whose medical status isunstable
in the antenatal, delivery, and postpartum periods.
Sonography is the imaging modality of choice for
diagnosing maternal-related abnormalities both during and following pregnancy and delivery. Pelvic
ultrasound has long been the mainstay for evaluation
of the female pelvis. It is widely used during pregnancy in countries where antenatal care is available.
Most pregnant women are referredfor ultrasound
study to confirm gestational age and to rule out fetal
malformations, abnormal placentation, and uterine
and cervical abnormalities. At University Hospitals
of Cleveland, Case Western Reserve University, a
tertiary care medical facility, more than 12,000 obstetric ultrasound studies are performed yearly. About
13% of the total studies are performed in an emergency obstetricsetup. This article describes the
emergency conditions during pregnancy and the
immediate postpartum period that might lead to a
life-threatening situation for the pregnant patient or
her fetus, and the spectrum of imaging findings
associated with these conditions.

* Corresponding author.
E-mail address: noam@cwru.edu (N. Lazebnik).

Ultrasound examinations in emergency situations
areordered to obtain specific, limited information
when it is necessary or impossible to perform a
complete fetal, placental, or pelvic organ survey.
Limited examinations in antepartum and intrapartum
emergency settings may include identification of
fetal number, fetal presentation, presence or absence
of fetal cardiac activity, localization of the placenta,
assessment of amniotic fluid volume,and a biophysical profile. The relevant clinical information can be
obtained by performing transabdominal study, transvaginal study, or combination of the two modalities.
Occasionally, additional ultrasound studies are needed
in cases of medical or surgical complications of the
pregnant patient. Examples of such disorders include
renal and gastrointestinal abnormalities and maternal
vascularabnormalities.

Sonographic technique
Modern ultrasound devices have variable-focus
depths that allow the examiner to study structures
in the near or far field as needed without changing
transducers. A 2- to 5-MHz and 4- to 9-MHz transducer for transabdominal and transvaginal study,
respectively, is very well suited. For a pelvic sonogram, performed transabdominally, the patient’s urinarybladder should be distended. A full bladder
usually is unnecessary. The more advanced the pregnancy, the lesser the need for a full bladder. Whenever cervical and lower uterine segment or pelvic
organs images are needed, endovaginal scanning is
superior to transabdominal scanning. Improved visualization may be achieved using the vaginal approach, because the transducer is brought closer to0033-8389/04/$ – see front matter D 2004 Elsevier Inc. All rights reserved.
doi:10.1016/j.rcl.2004.01.006

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N. Lazebnik, R.S. Lazebnik / Radiol Clin N Am 42 (2004) 315–327

the area being examined. It can be very helpful in
studying the lower uterine segment and its relation
to the placenta, evaluating the uterus, or measuring a
cyst in an ovary in the early stage of pregnancy. The...