Pregnant expectant mothers need to undergo various examinations, almost once a month for prenatal check ups, in order to assess the health status of both the expectant mother and the fetus. Among numerous fetal examinations, the most common is ultrasound examination. However, some pregnant women have found that the gestational age detected by ultrasound is larger than the actual gestational age. Does this situation exist?
Is the gestational age on ultrasound greater than the actual gestational age?
Ultrasound detection is based on the size of the fetus to calculate the gestational age. If the fetus grows too small or too large, there may be errors.
Time arrangement of prenatal ultrasound
First examination: At 18-20 weeks of pregnancy, it can be determined whether it is a normal intrauterine pregnancy, single or twin pregnancy, etc.
Second examination: Three dimensional or four-dimensional ultrasound at 28-30 weeks of pregnancy. At this point, it is possible to understand the development of the fetus, whether there are any surface deformities, and further understand the position and amniotic fluid volume of the fetus.
Third examination: At 37-40 weeks of pregnancy, the fetal position, fetal size, placental maturity, and presence of umbilical cord entanglement can be determined for the final evaluation before delivery. So how many ultrasound scans should be done during pregnancy. This is not absolute, it depends on the specific situation of the pregnant woman. If it is not necessary, do not undergo frequent B-ultrasound examinations. Excessive ultrasound is detrimental to the fetus, as ultrasound can cause temporary suppression of the brain and also inhibit ovarian development in female fetuses, resulting in varying degrees of inhibition of fetal growth and development.
Moreover, performing ultrasound to differentiate between males and females can cause harm to the fetus. That's because prolonged exposure to a specific part of the fetus can affect its development due to the thermal effect of ultrasound. The first time should start from the diagnosis of early pregnancy. If no abnormalities are found for the first time, prenatal check ups should be conducted every 4 weeks from 20-36 weeks, and once a week after 36 weeks, for a total of 9 prenatal check ups.
The above is the reason why expectant mothers who undergo ultrasound examination during pregnancy have a gestational age larger than the actual gestational age. In addition, due to multiple ultrasound examinations during pregnancy, expectant mothers must pay attention to the precautions before the ultrasound examination and never go for the examination hungry, otherwise the examination results may be inaccurate.
