Ectopic pregnancy refers to the condition where the embryo implants outside the uterine cavity, most commonly in the fallopian tubes. A normal pregnancy test may still show a positive result in cases of an ectopic pregnancy. However, around 40 days after missed menstruation, no normal gestational sac can be seen inside the uterine cavity. Diagnosis generally requires a combination of blood HCG level monitoring and ultrasonographic examination. Once an ectopic pregnancy is confirmed, medical abortion is not viable, as it cannot expel the embryo from the body. Other surgical interventions are necessary for treatment.