ultrasound diagnosis of fatal anomalies

MULTIPLE PREGNANCY
Growth Restriction in Twins
Definition: Growth restriction is diagnosed if the
sonographically estimated fetal weight lies
belowthe 5th percentile. This is usually associated
with disparity in the size of the twins.
The values measured are compared with the
standard fetal weight charts for twins.
neonatal stage are frequent complications. In addition,
polycythemia, hypoglycemia, and hyperbilirubinemia
may be present.
Prognosis: Growth-restricted infants have a
higher morbidity and mortality.
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Incidence: Occurs in 12–47% of twin pregnancies.
Ultrasound findings: One or both twins are small
for gestational age; the thoracoabdominal circumference
is most frequently affected. Oligohydramnios
is a frequent accompanying feature.
Twin-to-twin transfusion syndrome has to be
considered in the differential diagnosis, but this
can be excluded if the pregnancy is not monochorionic
(TTTS occurs almost exclusively in
monochorionic pregnancy). If the pregnancy is
monochorionic, then an absence of hydramnios,
cardiac failure, and hydrops (characteristic for
the recipient twin in TTTS) in the larger twin excludes
TTTS.
Clinical management: Karyotyping, search for
infections (TORCH). The high frequency of chromosomal
and structural anomalies in twin pregnancies
has to be taken into account. Frequent
scanning of fetal growth using color-coded
Doppler imaging and echocardiography at short
intervals. Premature delivery may be an option,
depending on the gestational age and severity.
Administration of cortisone to promote maturation
of the lungs has not shown any clear benefit
in twin pregnancies. Some studies have reported
a beneficial effect of additional administration of
thyrotropin-releasing hormone (TRH).
Procedure after birth: Fetal distress during labor
and respiratory insufficiency in the immediate
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