In which condition would hCG levels be lower than expected for the gestational age?

In ectopic pregnancy, human chorionic gonadotropin (hCG) levels are often lower than expected for the gestational age due to the abnormal implantation of the fertilized egg outside the uterus, commonly in the fallopian tube. In a typical intrauterine pregnancy, hCG levels rise significantly and consistently, reflecting the growing placenta and embryo. However, in an ectopic pregnancy, due to the compromised environment and failure to establish a viable implantation site, hCG levels may increase but will not reach the expected levels typically seen in a standard intrauterine pregnancy.

This situation can lead to misinterpretation of the hCG levels as they may not reflect the expected trajectory of a healthy early pregnancy, prompting further investigation and management. Monitoring hCG levels in suspected ectopic cases is crucial, as rising levels remain a concern, but the values would not adhere to the normal escalation pattern seen in viable intrauterine pregnancies.