Generally speaking, the meaning of anomaly screening is color Doppler anomaly screening. The total number of anomaly screening ultrasound examinations during pregnancy is divided into two times, one is from 21 to 24 weeks of pregnancy, and the other is to perform an ultrasound examination at 28 to 32 weeks of pregnancy. Pregnant women should have a color Doppler ultrasound examination within the time specified by the doctor, and now it is possible to have a three-dimensional or four-dimensional color Doppler ultrasound examination.

The main purpose of the color Doppler ultrasound examination is to check for fetal malformations.

1. Fetal facial malformations: such as cleft lip and palate.

2. Neurological abnormalities: anencephaly, hydrocephalus, microcephaly, spina bifida, meningocele, etc.

3. Digestive system malformations: umbilical hernia, visceral ectopia, intestinal atresia, megacolon, etc.

4. Urinary tract malformations: hydronephrosis, polycystic kidney, megacystis, urethral obstruction, etc.

5. Other malformations: short limbs, symbrachydactyly, tetralogy of Fallot, etc.