Reference Range for hCG in Early Pregnancy

After a woman becomes pregnant, her body undergoes a series of hormonal changes—certain hormones that were previously absent begin to appear, and levels of others rise significantly. As is widely known, pregnancy is commonly confirmed by detecting human chorionic gonadotropin (hCG) in urine or blood. So, what is the normal reference range for hCG in early pregnancy?

Normal Reference Range for hCG in Early Pregnancy

In a normal pregnancy, serum hCG levels exceed 5 IU/L by day 8–10 post-fertilization, and should surpass 100 IU/L around day 31 of gestation. As pregnancy progresses, serum hCG peaks between weeks 8–10, reaching approximately 50,000–100,000 IU/L. Thereafter, hCG levels gradually decline; by approximately week 14 of gestation, serum hCG typically falls to 10,000–20,000 IU/L. These values can be used both to estimate gestational age and to assess the status of the pregnancy.

Human chorionic gonadotropin (hCG) is a glycoprotein hormone secreted by the trophoblastic cells of the placenta, composed of α- and β-subunits. The intact hCG molecule is produced by the syncytiotrophoblast layer of the placental chorion. Its primary physiological role is to stimulate the corpus luteum, thereby sustaining the secretion of estrogen and progesterone. This supports decidualization of the endometrium and promotes placental development and maturation.

It is recommended to visit a hospital for a blood hCG test approximately eight days after intercourse. Results obtained beyond this timeframe are generally considered reliable. We hope this information proves helpful! Wishing you good health and happiness!