Prenatal Ultrasound Screening for External Ear Abnormality in the Fetuses

Table 1

Detection rate of fetal external ear in different gestational ages for routine obstetric ultrasonography.

Gestational age (week)	Fetus (n)	Number of auricles (n)	Detection rate (%)
16~<20	4825	9650	94.11
20~<24	7892	15784	95.19
24~<28	7256	14512	87.45
28~<32	6621	13242	77.56
32~<36	6324	12648	68.84
36~40	4245	8490	50.73
Total	37163	74326	78.98