Nuchal-fold thickening in Down syndrome fetuses: transient appearance and spontaneous resolution in the second trimester.
To elucidate the cause of the wide variation of sensitivity of the nuchal-fold thickness (NFT) for a noninvasive prenatal screening test for fetal Down syndrome, we consecutively measured the NFT throughout pregnancy in eight fetuses with Down syndrome and 100 normal fetuses (negative controls) using video-recorded ultrasonography. When 6 mm was set as the cutoff value, 6/8 Down syndrome fetuses showed a NFT above this value at least once during pregnancy. However, the thickening was transient in 5 of them and resolved spontaneously during the second trimester. Persistent thickening of nuchal-fold was only observed in one fetus. From the results of the present study, we recommend that the NFT be measured repetitively during the first and second trimesters as a noninvasive prenatal screening test for Down syndrome.
Department of Gynecology and Obstetrics, Kyoto University Faculty of Medicine, Japan.
H
H
Itoh
Y
Y
Ihara
N
N
Sagawa
T
T
Mori
E
E
Natsuyama
D004314:Down Syndrome / Q000000981:diagnostic imaging / Q000196:embryology*; D005260:Female; D005333:Fetus / Q000033:anatomy & histology; D005865:Gestational Age; D006801:Humans; D009333:Neck / Q000002:abnormalities / Q000196:embryology; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D016216:Ultrasonography, Prenatal