A negative second trimester triple test and absence of specific ultrasonographic markers may decrease the need for genetic amniocentesis in advanced maternal age by 60%.
OBJECTIVE
A study was conducted to evaluate the sensitivity of combining a second trimester triple test and targeted ultrasound in order to detect Down syndrome in women undergoing amniocentesis over 35 years of age.


METHODS
Women over 35 years of age underwent a triple test and an ultrasound examination for chromosomal markers immediately prior to genetic amniocentesis.


RESULTS
One thousand and six women were examined. Four hundred and thirty seven were triple test-positive and in 195 cases ultrasonographic abnormalities were observed. Thirteen had Down syndrome and eight had other chromosomal abnormalities. All women with Down syndrome babies were triple test-positive and seven also had ultrasonographic markers. Three of eight women who had babies with chromosomal aberrations other then Down syndrome were also triple test-positive.


CONCLUSIONS
The use of the triple test as a screening tool in our population would reduce the number of amniocenteses by 60%, while no cases of Down syndrome would be missed. Ultrasonographic markers have added little to this population. Three non-Down syndrome chromosomal abnormalities and two Down syndrome mosaic cases would be missed by this approach.
Rosen
D J D
DJ
Department of Obstetrics & Gynecology, Meir Hospital, Kfar-Saba, Israel. doron_rosen@hotmail.com
Kedar
I
I
Amiel
A
A
Ben-Tovim
T
T
Petel
Y
Y
Kaneti
H
H
Tohar
M
M
Fejgin
M D
MD
D000328:Adult; D000649:Amniocentesis; D006063:Chorionic Gonadotropin / Q000097:blood; D002869:Chromosome Aberrations; D004314:Down Syndrome / Q000175:diagnosis*; D004964:Estriol / Q000097:blood; D005260:Female; D005865:Gestational Age; D006801:Humans; D007621:Karyotyping; D008423:Maternal Age; D008875:Middle Aged; D011247:Pregnancy; D018566:Pregnancy, High-Risk; D011296:Prenatal Diagnosis; D012680:Sensitivity and Specificity; D016216:Ultrasonography, Prenatal; D000509:alpha-Fetoproteins / Q000032:analysis
D006063:Chorionic Gonadotropin; D000509:alpha-Fetoproteins; D004964:Estriol