research day - University of Toronto Department of Obstetrics and ...

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ABSTRACT #P-A4
PHENOTYPE OF EARLY ONSET INTRAUTERINE GROWTH RESTRICTION (IUGR)
Nihal Al Riyami [F](1), Leslie Proctor(1)Yoav Yinon(1), Elizabeth Winsor(2), John Kingdom(1)
(1)Department of Obstetrics and Gynaecology (Division of Maternal Fetal Medicine);
(2)Department of Laboratory Medicine and Pathobiology; Mount Sinai Hospital; University of
Toronto.
Objectives: To demonstrate that all early onset IUGR pregnancies due to placental diseases are
asymmetrical. To determine the incidence and pattern of chromosomal abnormalities in fetal
growth restriction and demonstrate that early onset IUGR due to placental disease more closely
mimics triploidy than trisomy 18.
Methods: A retrospective chart review from 2001 to 2008 using the cytogenetics database for the
prenatal diagnosis of trisomy 18 or triploidy by invasive fetal testing of amniotic fluid, placental
sample by chorionic villous sample (CVS) or fetal blood sample. A retrospective review of all
early onset IUGR due to placental disease, from week 18 to week 32+6 using the placental clinic
database. All feuses with an absent or reversed end diastolic flow (AREDF) of the umbilical artery
within a week of delivery at Mount Sinai Hospital were included. The head over the abdominal
circumference ratio (HC/AC) was measured. An elevated ratio indicated fetal asymmetry.
Results: 73 women with placental mediated early onset IUGR were identified, and 62% of the
fetuses had a HC/AC ratio above the 95 th percentile for gestational age, suggesting that the
majority are asymmetrical growth restricted. 8 out of 9 patients with triploidy were asymmetrical
IUGR. There were 50 patients with trisomy 18 out of witch, 18 were asymmetrical IUGR and 32
were symmetrical IUGR; this was significantly different from the early onset IUGR group
(p=0.0306).
Conclusions: Early onset IUGR due to placental disease presented mostly as an asymmetrical
pattern and this mimicked triploidy rather than trisomy 18 patients.