Fetal cells in the uterine cervix: a source for early non-invasive prenatal diagnosis.
Various non-invasive techniques for prenatal diagnosis have been under investigation. We evaluated the success of fetal sexing using a non-invasive technique for obtaining fetal cells, uterine cervix brushing, in combination with FISH. Thirty pregnant women who completed between 6 and 10 weeks of gestation and who were scheduled to undergo pregnancy termination were included in the study. A Pap smear cytobrush was inserted through the external os to a maximum depth of 2 cm and removed while rotating it a full turn. The material that was caught on the brush was spread on four microscope slides. Two-color FISH was used for fetal sexing. Following pregnancy termination, a placental sample was used for full karyotyping. In 29/30 cases FISH diagnosis was confirmed by chromosomal analysis. The only male case in which a Y chromosome was not seen was from a pregnancy of 6 weeks 6 days gestational age. One case was mosaic of 46,XY/47,XXY (25%). In most cases (7/13) the Y chromosome was already identified in the first analyzed slide. With the use of a cytobrush fetal cells can be easily obtained for the purpose of prenatal diagnosis of chromosomal disorders.
Fejgin
M D
MD
Genetic Institute, Meir Hospital, Kfar-Saba, Israel.
Diukman
R
R
Cotton
Y
Y
Weinstein
G
G
Amiel
A
A
D002584:Cervix Uteri / Q000166:cytology*; D005260:Female; D005333:Fetus / Q000166:cytology*; D005865:Gestational Age; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008297:Male; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods; D012732:Sex Determination Analysis / Q000379:methods