Gynecologic ultrasound includes both routine ultrasound and transvaginal ultrasound. Routine ultrasound is the most common and is performed by placing the ultrasound probe in the lower abdomen to observe the pelvic organs, focusing on the uterus, adnexa and pelvis. You need to drink about 1000ml of water half an hour to one hour before the examination and hold your urine to the maximum. This is because only when the bladder is filled to a certain level can the shape of the uterus and ovaries be clearly shown by the light and dark contrast of the images. Transvaginal ultrasound is performed with a special probe on the ultrasound machine. A film is placed over the vaginal ultrasound probe and the probe is inserted into the vagina for examination. Because the probe is positioned close to the uterus and ovaries, the images are clear with high resolution and the results are more accurate. In addition to this, it has the added advantage of not requiring urine to be held, which is a relative time saver and a good feeling for the patient. Vaginal ultrasound during early pregnancy is obviously necessary to monitor the location of the gestational sac and the growth and development of the fetus. Vaginal ultrasound during early pregnancy has the following benefits: 1. It provides a clear picture of the normal location of the gestational sac and clarifies whether the pregnancy is intrauterine or ectopic. Ectopic pregnancy can increase in size as the gestational week grows and the trophoblast cells erode the bed site, causing rupture and bleeding in the organs (commonly the fallopian tubes), resulting in anemia and even death due to massive blood loss, which is one of the common emergency cases in obstetrics and gynecology. This is one of the common emergencies in obstetrics and gynecology. 2. Verify the gestational week and determine the development of embryo. Judging the gestational age based on the average diameter of the gestational sac, the size of the fetal germ, and the head-rump length of the fetus can help determine the fetal development during mid- to late-term pregnancy. Ultrasound uses a real-time imaging system to clearly observe the fetal heartbeat. If the fetal bud is larger than 9 mm on transabdominal ultrasound (5 mm on transvaginal ultrasound), a fetal heartbeat should be seen. If no fetal heartbeat is seen, it indicates the possibility of embryonic arrest and should be reviewed regularly. Once the embryo stops developing, it is called an abnormal miscarriage and the embryonic tissue should be surgically removed as soon as possible. 3. To determine the number of embryos, this is the most accurate method for early diagnosis of multiple pregnancies. With the widespread use of assisted reproduction technology, twin and triplet pregnancies have become commonplace. If there are more than 2 pregnancies, not only the obstetric complications such as gestational hypertension increase significantly, but also the risk of preterm delivery, and less full-term newborns are born, so early surgical reduction should be performed to ensure the safety of mother and fetus. 4. Observe the early development of the placenta. At 6 weeks of gestation, the primordial placenta begins to form between the lobulated chorionic membrane of the embryo and the underlying metaplasm of the uterus, and at 8 weeks of gestation, the placenta can be identified. Ultrasound also helps to identify trophoblastic disease in pregnancy, commonly known as staphylocytosis. 5. Early detection of uterine and adnexal abnormalities. To know if there are uterine abnormalities, myomas and swellings in the adnexal area, etc. Thus, it can be seen that ultrasound does have important applications in the diagnosis of early pregnancy and differential diagnosis of diseases. Does ultrasound have any effect on the fetus? I believe this is the main concern of parents-to-be. It is generally believed that ultrasound is a kind of sound wave transmission, there is no ionizing radiation and electromagnetic radiation, there is no harm to human tissue. In fact, the medical use of ultrasound is low intensity, below the safety threshold; the short duration of early pregnancy examination, generally less than 3 minutes, and non-scheduled glide examination, is very safe for the embryo, and so far there are no reports of fetal malformations caused by ultrasound examination. Put another way, the few ultrasounds necessary in early pregnancy may not be as harmful as the intensity of radiation you get from using microwave ovens and cell phones in your life? Most diseases have some precursor symptoms, such as ectopic pregnancy, spontaneous abortion, gravida and other pregnancy-related conditions, often with vaginal bleeding and abdominal pain. Therefore, the occurrence of vaginal bleeding and abdominal pain suggests an abnormal situation, and the possibility of the above diseases should be considered, and you should consult a doctor as soon as possible to perform an ultrasound examination to clarify the diagnosis so as not to delay the condition. In addition, for those who are at high risk of ectopic pregnancy, after multiple abortions or medication abortions, history of acute and chronic pelvic inflammatory disease, poorly patent fallopian tubes, use of emergency contraceptive pills, etc., it is best to have a vaginal ultrasound examination as soon as possible to clarify the location of the pregnancy sac. We need to think rationally about vaginal ultrasound, evaluate its advantages and disadvantages, and perform the test early when it is needed, but also pay attention to avoid unnecessary repeat tests when there is no indication for the test.