Transcervical sampling as a means of detection of fetal cells during the first trimester of pregnancy.
OBJECTIVE
Our aim was to evaluate the detection of fetal cells from transcervical samples by means of fluorescence in situ hybridization analysis.


METHODS
Forty-seven women undergoing first-trimester termination of pregnancy were recruited for transcervical sampling and 16 were recruited for endocervical mucus aspiration. Subjects were asked to assess the discomfort of the procedure. Fluorescence in situ hybridization analyses were performed with X and Y chromosome-specific probes. Results were compared with those of conventional chromosomal analysis.


RESULTS
Male signals (XY) were observed in 19 of 25 male fetuses (76%), and female signals (XX) were observed in 21 of 22 female fetuses. There was a significant variation between operators in cell retrieval. With mucus aspiration only 37.5% of male fetuses were correctly identified. The subjects did not find the procedure uncomfortable and reported that it was comparable to having a cervical smear taken.


CONCLUSIONS
Transcervical irrigation correctly identified the sex of 76% of male fetuses, but it still has considerable operator variability. This variability might be reduced by improved catheter design.
Daryani
Y P
YP
Department of Medical Genetics and the Department of Obstetrics and Gynaecology, St George's Hospital Medical School. London, United, Kingdom.
Barker
G H
GH
Penna
L K
LK
Patton
M A
MA
D002582:Cervix Mucus / Q000166:cytology; D002584:Cervix Uteri / Q000166:cytology*; D005189:False Positive Reactions; D005260:Female; D005333:Fetus / Q000166:cytology*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D011247:Pregnancy; D012732:Sex Determination Analysis; D013396:Suction; D007507:Therapeutic Irrigation; D014960:X Chromosome; D014998:Y Chromosome