The major examination refers to pregnant women in 22~26 weeks of pregnancy to the hospital for four-dimensional ultrasound examination, this examination is more accurate and intuitive, if the fetus is abnormal, the probability of detecting malformations will be greater, if the fetus is normal, it will not be detected malformations.
Four-dimensional ultrasound examination mainly examines the fetal limbs, internal organs, head, amniotic fluid, umbilical cord, etc., which can detect most of the malformations of the fetus, and it is a more accurate way in the detection of malformations.
If the fetus has congenital heart disease, polydactyly, etc., it can be diagnosed through this test, and if the fetus is abnormal, the probability of detecting malformations is higher.
Therefore, it is recommended that pregnant women undergo adequate examinations during pregnancy to ensure the health of the fetus and take timely intervention if there are any abnormalities.