Prenatal Ultrasonographic Findings in “Trisomy 13”
Somsri Pitukkijronnakorn MD*, Patama Promsonthi MD*, Panyu Panburana MD*, Rasig Rangsiprakarn MD*, Apichart Chittacharoen MD*
Affiliation : * Department of Obstetrics and Gynaecology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok
Objective : To evaluate the accuracy of prenatal ultrasonographic diagnosis in fetuses with trisomy 13.
Material Method: The present study consisted of all fetuses diagnosed of trisomy 13 and delivered at
Ramathibodi Hospital between 1997 and 2006.
Results : There were 15 cases of trisomy 13. Twelve cases (80.0%) were detected by prenatal ultrasonographic
examination, and 3 cases (20.0%) were missed. Mean maternal age was 31.4 years old. Sixty-six percent were
diagnosed in 2nd trimester (mean 19.4 weeks). The earliest gestational age for detection was 12 weeks 6 days.
The most common abnormal ultrasonographic findings were holoprosencephaly (46.7%), and facial defects
(40.0%).
Conclusion : The accuracy of prenatal sonographic diagnosis in trisomy 13 fetuses was 80%. The most sensitive
prenatal ultrasonographic findings in trisomy 13 were holoprosencephaly and facial defects.
Keywords : Trisomy 13, Prenatal diagnosis, Ultrasonography
