amniotic fluid alpha-fetoglobin

It is synthesized by fetal liver cells and yolk sac, and its concentration gradually rises from the beginning of pregnancy. The gestational age reaches a peak at 16 to 20 weeks, reaching 40 mg/L. It gradually decreases after 20 to 22 weeks, and drops to about 25 mg/L after 32 weeks. And has been maintained until the full term. Is a competitive inhibition reaction, the amniotic fluid or AFP standard is added with a certain amount of 125I-AFP and a certain amount of AFP antiserum solution, mixed and incubated at 37 ° C, then added polyethylene glycol solution, AFP and antibody The complex produces a precipitate. Basic Information Specialist classification: maternity check check classification: biochemical examination Applicable gender: whether women are fasting: not fasting Tips: If you are testing amniotic fluid, you should not add thermal fluid. Normal value Early pregnancy 20 ~ 48mg / L (20 ~ 48μg / ml). Clinical significance The amniotic fluid alpha globulin value is 10 times higher than the normal value, indicating that the fetus has an open neural tube abnormality or is a brainless child. High results may be diseases: pediatric neural tube defects, no brain care matters 1. The analysis box is more accurate in the range of 10～200μg/L, and it is expected to use this range as much as possible. 2, if the amniotic fluid is measured, it should be added without heating solution, and 0.1ml normal human serum should be added to make the total reaction volume still 0.4ml. Inspection process Amniocentesis was used to collect appropriate amniotic fluid samples and immediately sent for inspection. The detection operations are as follows: 1. Take the test tube for numbering. 2. After adding PEG, place it for 10 minutes. 3. Determine the total radioactivity (T) of each tube. 4. Centrifuge at 3000r/min for 15min. 5. Carefully aspirate the supernatant. 6. Determine the radioactivity (B) of each tube precipitate. Not suitable for the crowd 1. Pregnant women should not be tested when they have a cold. 2, amniocentesis need to get the consent of the pregnant woman and their families, no check for appropriate symptoms should not be carried out. Adverse reactions and risks 1, maternal injury: puncture needle stab wound blood vessels caused by abdominal wall hematoma uterine subserosal hematoma. Occasionally, amniotic fluid enters the maternal blood circulation from the puncture hole and causes amniotic fluid embolism. The bladder was not emptied before the puncture, and the bladder was injured. 2, damage to the fetus, placenta and umbilical cord: puncture needle damage to the fetus can occur bleeding, stab wounds and umbilical cord can also occur bleeding or hematoma. Therefore, the source of bleeding should be identified when taking hemorrhagic amniotic fluid. If you suspect that you are from a fetus, you should continue to listen to the fetal heart. 3, amniotic fluid leakage: postoperative amniotic fluid leakage from the needle hole, resulting in too little amniotic fluid, affecting fetal development, and even cause miscarriage or premature birth. 4, abortion or premature delivery: the incidence of abortion or premature birth 0.1% -0.2%, often occurred within one week after surgery, even after the puncture, premature rupture of membranes leading to premature delivery. 5, intrauterine infection: postpartum may have maternal fever. Intrauterine infection can cause abnormal fetal development, or even fetal death. Therefore, amniocentesis should be strictly aseptic.