Generally, a pregnant woman can be examined about/0/8-28 weeks pregnant. Four-dimensional color Doppler ultrasound can display the color, face and development of various organs of the fetus, and even the state of the fetus in the mother can be observed, which can diagnose fetal malformations such as cleft lip, cleft palate, skeletal dysplasia and cardiovascular malformation at an early stage. Understand a fetal movement process of fetal intrauterine dynamics, and then dynamically record the fetal intrauterine state for permanent commemoration. Generally, Down's screening is done around 17 weeks, that is, fetal neural tube malformation is checked, and a three-dimensional B-ultrasound can be done from 24 to 26 weeks, so that the development of the fetus can be seen intuitively, and whether the fetus has cleft lip and palate and visceral development can be seen.

Secondly, it is best to have an ultrasound examination at the pregnancy 18~20 weeks. During this period, all organs of the fetus have been fully developed, and careful B-ultrasound examination can show whether every important organ is abnormal. Fetal malformation can be found early, pregnancy can be terminated in time, and the impact on the mother's body is also small. In the future, if there is no abnormality, you can wait until the last few weeks of pregnancy to do another B-ultrasound examination to estimate the size of the fetus and understand the position of the placenta and the amount of amniotic fluid. Regular pregnancy tests should be done during pregnancy to closely observe the development of the fetus. Color Doppler ultrasound examination is necessary. Generally, obvious limb abnormalities or deformities can be clear, but they are not absolute. It is suggested that it is better to follow the opinions of clinicians according to your own situation.

Then, although the prenatal examination can screen most malformations, some malformations can't be detected, such as hydrocephalus and congenital blindness (the fetus rarely opens its eyes in amniotic fluid), and congenital hearing impairment (now the fetus has to have a hearing test at birth)? Abnormal limbs (such as polydactyly and syndactyly). ) dwarfism (usually in the third trimester of pregnancy or after birth) Congenital metabolic abnormality (usually found after birth)? Gastrointestinal obstruction (difficult to find in the second trimester) visceral abnormality (fetal visceral abnormality may be found after birth) and so on.

At present, the ultrasonic screening items of fetal macromastia generally include: skull halo, lateral ventricle, cerebellum, posterior fossa cistern, spine, neck soft tissue, orbit, oral lip, four-chamber heart, chest cavity, gastric vesicle, intestine, kidney, bladder, humerus and upper limbs of ulna and radius, femur and lower limbs, tibia and fibula, wrist, ankle and umbilical blood vessels. For many fingers, small ears can't see.

To sum up, large-scale deformity is not omnipotent, but it is absolutely impossible not to have large-scale deformity. Choose a reliable hospital to get greater protection. The above is my answer to the check-up of large ovulation during the prenatal examination and how many weeks of pregnancy, hoping to provide some help to the needy friends. Good luck with your pregnancy.