AFP is a glycoprotein that normally comes from the liver cells of the embryo and disappears from the blood about two weeks after birth, so the amount of AFP in normal human serum is still less than 20 micrograms/liter. AFP is mainly synthesized in the fetal liver, with a molecular weight of 69,000, and accounts for 1/3 of the total plasma protein at 13 weeks of gestation. it reaches its peak at 30 weeks of gestation and gradually declines thereafter, with the concentration in plasma at birth being about 1% of the peak, about 40 mg/L, and approaching the adult level (below 30 μg/L) at the age of one week. clinically, AFP is mainly used to assist in the diagnosis of hepatocellular carcinoma and to observe However, the specificity of this indicator is not high, not to say that a high level of this indicator means liver cancer, many diseases can cause this elevation, and the reference value may vary slightly from hospital to hospital. Therefore, there is no need to panic if there is a mild elevation of alpha fetoprotein, and it does not necessarily mean that you have cancer. AFP in maternal amniotic fluid or maternal plasma can be used for prenatal monitoring of the fetus. For example, in neural tube defects, cremasteric cleft, and anencephaly, AFP can enter the amniotic fluid from an open neural tube and cause its level to be significantly elevated in the amniotic fluid. AFP may also be elevated in amniotic fluid in cases of intrauterine death and congenital defects such as teratoma. In 85% of mothers with cremasteric cleft and anencephaly, plasma AFP is seen to be elevated at 16-18 weeks of gestation and is diagnostic, but must be combined with clinical experience to avoid false positive errors. In adults, AFP can be elevated in the serum of approximately 80% of patients with hepatocellular carcinoma, and in germ cell tumors a positive AFP rate of 50% is seen. It can also be elevated to varying degrees in patients with other gastrointestinal tumors such as pancreatic or lung cancer and cirrhosis of the liver. However, when hepatocellular carcinoma occurs, the function of producing this protein is restored and its level in the serum increases dramatically as the disease worsens, making AFP a specific clinical indicator for the diagnosis of primary hepatocellular carcinoma. In the past, it has been considered as a specific tumor marker for the diagnosis of primary hepatocellular carcinoma, with the role of establishing diagnosis, early diagnosis and differential diagnosis. In recent years, a large number of clinical but found that some patients with cirrhosis will have long-term AFP reaching thousands, but no signs of liver cancer for many years; meanwhile, it is found that about 20% of patients with advanced liver cancer still have AFP not more than 10 until their death. Patients with liver disease should prevent elevated AFP from the following aspects: ① Treat the condition correctly and maintain an optimistic attitude. Once some people know that they have liver disease, they will be sad all day long, not knowing that depressed mood can reduce the body’s ability to resist disease and contribute to the deterioration of the disease. Therefore, maintaining an optimistic state of mind is crucial for patients with liver disease. ② Actively cooperate with the doctor’s treatment to stop or delay the further development of the disease. ③Reasonable diet. Patients with hepatitis B should preferably arrange a diversified and balanced diet, especially they should avoid eating moldy peanuts and soy products, and eat less animal fat, fried food and salted meat. ④Prohibition of smoking and alcohol. Alcohol consumption can contribute to the early development of cirrhosis and increase the incidence of liver cancer in patients with liver disease. Therefore, patients with liver disease should unconditionally abstain from alcohol, liquor and beer are within the scope of prohibition. Smoke contains many toxic substances that can damage liver function and inhibit liver cell regeneration and repair. ⑤ Do not overexert yourself. Overexertion can consume a lot of nutrients, thus weakening the liver’s resistance to disease, so that the rapid spread of hepatitis virus, aggravating the disease. ⑥ abstain from sexual life. Acute hepatitis B, chronic hepatitis B acute attack, chronic active hepatitis B, active cirrhosis patients, should temporarily avoid sex, indulge in sex at this time, can only aggravate the disease; hepatitis B virus carriers, mild chronic hepatitis B patients, patients with cirrhosis of the resting phase can have sex, but should control the frequency, such as young people should be 1 to 2 times a week, middle-aged people should be 1 to 2 times every 1 to 2 weeks. Middle-aged and elderly patients should be 1 to 2 times a month. In short, patients with liver disease should not feel fatigue the next day when they have sex. (7) Avoid the indiscriminate use of drugs. The liver is an important organ of the body, and many drugs are metabolized in the liver. The indiscriminate use of drugs will certainly increase the metabolic burden of the liver.