1Department of Obstetrics & Gynecology, College of Medicine Pochon CHA University 2Human Genetics Laboratory, College of Medicine Pochon CHA University
Published online: March 1, 2001.
ABSTRACT
PURPOSE: To evaluate the significance of fetal choroid plexus cysts (CPCs) in the second trimester of pregnancy. MATERIALS and METHODS: Eighty-nine cases of isolated CPCs were prospectively followed up and 5 consecutive pregnancies of trisomy 18 were analyzed. Isolated CPCs were defined as fellows: 1) there were no other abnormalities except CPCs on the detailed ultrasound. 2) the mother did not have any risk factors requiring amniocentesis. We compared maternal age, gestational age at time of detection, and the characteristics of CPCs in the groups of isolated CPCs and trisomy 18. We evaluated the autopsy findings or sonographic abnormalities in the group of trisomy 18. RESULTS: Maternal and gestational age were not different in both groups (29 +/- 2.1 vs 31 +/- 3.9 years old; 19 +/- 1.8 vs 19 +/- 1.3 week; p>0.05). The size of isolated CPCs was smaller than that of trisomy 18 (6.5 +/- 2.5 vs 12.6 +/- 4.6 mm; p<0.01). All of isolated CPCs had disappeared and there was no trisomy 18. In the group of trisomy 18, all of them had CPCs and at least one other associated abnormalities. CONCLUSION: The risk of trisomy 18 in cases of isolated CPCs was very low. In this setting, the detailed ultrasound examination rather than the routine karyotyping is mandatory.