The HCG (human chorionic gonadotropin) value of about 1000 U/L indicates that the pregnant woman should be in the 4th-5th week of pregnancy, although the HCG value is not an accurate basis for determining the week of pregnancy, but because HCG appears in the blood and urine when a woman is pregnant, there are slight differences in HCG values in different weeks of pregnancy. HCG begins to be secreted about 6 days after fertilization, and an increase in HCG values will be detected about 1 week after menopause, in HCG values can reach about 1000 U/L in the 4th-5th weeks of pregnancy. The normal HCG value is multiplied and peaks during the 8-12 weeks of pregnancy and continues to decrease gradually for about 2 weeks, with the HCG value basically decreasing to 0 during the 2-4 weeks after delivery. in addition, an HCG value of 1000 U/L may be due to medical reasons, including incomplete abortion, gravida, chorioepithelial carcinoma, etc. An abnormal increase in HCG concentration in blood test or urine test requires prompt medical attention to identify the cause and choose the appropriate treatment.