Ultrasound is a kind of ultrasound examination, a non-surgical diagnostic test, an emerging discipline that has become an indispensable diagnostic method in modern clinical medicine. Ultrasound examination during pregnancy can observe the physiological activities of the fetus. How long can ultrasound be done in pregnancy? Ultrasound can only see the gestational sac after 5 weeks of pregnancy, and the gestational sac detection rate reaches 100% at 6 weeks of pregnancy. The germ is visible at 6-7 weeks of gestation, and the primitive heart tube is visible at 49 days of gestation when the germ is 2 mm in diameter, and takes on a human form at 8 weeks of gestation. All organs are formed by the end of the 14th week. By the end of the 15th week, hair begins to appear and by the end of the 16th week, the uterus is approximately 16 cm. By the end of the 17th week, the baby’s movement is restricted and fetal movements occur. By the end of the 21st week, the second scan (which reveals the sex) is performed. The sex is known by the end of the 22nd week. Ultrasound done too early is not easy to see the shadow of the gestational sac, it is too small. Not every doctor can see it correctly and it depends on the experience of the person doing the imaging, the more you do, the better. Ideally, it should be visible only at 8-10 weeks of pregnancy.
It is best to avoid having an ultrasound too early or to have multiple ultrasounds, as it will theoretically shock the fragile, newly formed embryo, which is detrimental to the development of the embryo.