Overview
Clinical Frame
A positive pregnancy test confirms trophoblastic activity, not the location of implantation.
A positive pregnancy test confirms trophoblastic activity, not the location of implantation. An ectopic pregnancy is implanted outside the endometrial cavity; most are tubal, particularly in the ampulla. Interstitial, cervical, caesarean-scar, ovarian, and abdominal pregnancies are less common but can bleed severely. The first bedside question is not “What is the hCG?” It is “Could this patient be bleeding internally?” Sudden severe unilateral lower-abdominal pain, shoulder-tip pain, syncope or presyncope, rebound or guarding, tachycardia, and hypotension in a patient with a positive pregnancy test require emergency assessment for rupture. Establish large-bore intravenous access, begin resuscitation and blood-product preparation as indicated, and arrange immediate operative care through the local emergency and obstetric-gynaecology pathway. A stable patient with a positive pregnancy test and no pregnancy visible on transvaginal ultrasound has a pregnancy of unknown location (PUL), not an automatic diagnosis of ectopic pregnancy. That distinction protects a potentially desired viable intrauterine pregnancy from treatment based only on a laboratory threshold.