Fetal trunk and head volume in chromosomally abnormal fetuses at 11+0 to 13+6 weeks of gestation.
OBJECTIVE
To examine the pattern of growth in chromosomally abnormal fetuses at 11+0 to 13+6 weeks of gestation and compare the trunk and head volume to crown-rump length (CRL) in defining the growth deficit in such fetuses.


METHODS
The fetal trunk and head volume was measured using three-dimensional (3D) ultrasound in 140 chromosomally abnormal fetuses at 11+0 to 13+6 (median 12) weeks of gestation, and the values were compared to 500 chromosomally normal fetuses. In each chromosomally abnormal fetus, the observed fetal trunk and head volume was subtracted from the expected mean (delta value) of the chromosomally normal fetuses of the same gestational age, and this difference was expressed as a percentage of the appropriate normal mean. The Mann-Whitney U-test was used to determine the significance of differences between the chromosomally normal and abnormal groups.


RESULTS
In trisomy 21 (n=72) and Turner syndrome (n=14) fetuses, compared to chromosomally normal fetuses, the CRL for gestation was similar (P=0.335 and P=0.317, respectively), but the fetal trunk and head volume was about 10-15% lower (P<0.001 and P=0.004, respectively). In trisomy 18 (n=29), trisomy 13 (n=14) and triploidy (n=11), the deficit in volume was about 45% (P<0.001), whereas the deficit in CRL was less than 15% (P<0.001).


CONCLUSIONS
In the quantification of the degree of early growth impairment in chromosomally abnormal fetuses, measurement of the fetal trunk and head volume using 3D ultrasound may be better than measurement of CRL.
Falcon
O
O
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, UK.
Peralta
C F A
CF
Cavoretto
P
P
Auer
M
M
Nicolaides
K H
KH
D016022:Case-Control Studies; D015193:Chorionic Villi Sampling; D025063:Chromosome Disorders / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000196:embryology; D002881:Chromosomes, Human, Pair 12; D002887:Chromosomes, Human, Pair 18; D018568:Crown-Rump Length; D004314:Down Syndrome / Q000000981:diagnostic imaging / Q000196:embryology; D005260:Female; D006257:Head / Q000000981:diagnostic imaging* / Q000196:embryology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D007621:Karyotyping; D011237:Predictive Value of Tests; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D018709:Statistics, Nonparametric; D013909:Thorax / Q000000981:diagnostic imaging* / Q000196:embryology*; D014314:Trisomy; D014424:Turner Syndrome / Q000000981:diagnostic imaging / Q000196:embryology; D016216:Ultrasonography, Prenatal / Q000379:methods*