What is the level of serum human chorionic gonadotropin (hCG) during pregnancy?

Serum human chorionic gonadotropin (hCG) is an important indicator for detecting pregnancy. Generally, a serum hCG level greater than 25 U/L suggests possible pregnancy, although specific values may vary depending on the testing method, reagents used, and hospital standards. Under normal circumstances, the serum hCG level in non-pregnant women should be below a certain threshold (for example, some hospitals define this as 0–5 U/L or 0–20 U/L). If the test result exceeds this range, pregnancy is usually indicated. However, elevated hCG levels do not necessarily confirm a normal intrauterine pregnancy. Other clinical information, such as ultrasound examination, must also be considered for a comprehensive assessment. Additionally, hCG levels can vary significantly at different stages of pregnancy, typically rising rapidly and peaking at around 8–10 weeks gestation before gradually declining. Therefore, interpretation of hCG levels should take into account the specific gestational age and clinical context.