During pregnancy, women need to undergo multiple prenatal check ups, and some English letters appearing on the checklist may not be clear to some pregnant women about their meaning, such as the SD value on the checklist. So, what does the SD value of pregnant women mean?
1. The SD value checked during pregnancy is a ratio that mainly refers to the blood supply of the fetus. By analyzing the SD value data, it is possible to determine whether there are any abnormalities in the fetal umbilical cord and to understand whether the placental function is normal. The s value refers to the maximum blood flow velocity during fetal umbilical artery blood flow contraction, while the d value is the ratio of blood flow velocity to the end diastolic phase of umbilical blood flow.
2. During pregnancy, SD value testing is often conducted after 18 weeks of gestation, and specific reference data may vary depending on the gestational age. For example, during the 24th to 30th week of pregnancy, the SD value should be within the range of 2.5 to 5.0, and during the 36th to 40th week of pregnancy, the SD value should be within the range of 1.7 to 3.
3. If the SD value of a pregnant woman in the late stage of pregnancy exceeds 3, it often indicates that the fetus may have hypoxia in the uterus and requires timely symptomatic treatment. SD value testing is an important prenatal examination, and pregnant women should undergo this examination at the prescribed time. If there are slight abnormalities in the inspection results, it is important to strengthen prenatal examinations and closely observe.
