The patient who presents with an acutely ruptured ectopic pregnancy would typically exhibit symptoms of pain and hemodynamic instability. Pelvic pain may be extreme, sharp, or stabbing in nature, and shoulder tip pain can be associated with hemoperitoneum. Dizziness, lightheadedness, and loss of consciousness may occur from hypotension. Some women may present with symptoms related to gastrointestinal distress (e.g., nausea, vomiting, and diarrhea), and these should not be discounted as a possible ectopic pregnancy. Menses may be abnormal or absent, and this may not seem unusual as teens often have irregular bleeding patterns.

Classic signs of a ruptured ectopic pregnancy:

Laboratory tests: Laboratory testing requirements are minimal and are necessary only to confirm pregnancy, prepare for surgery, and rule out other pathologies.

Therapy: Fluid resuscitation should be started immediately and performed aggressively. Blood transfusion can also be initiated if appropriate. The primary method of management is surgery, both for diagnostic and therapeutic purposes. If the patient is Rh negative, she requires Rh immunoglobulin perioperatively. In the operating room (OR), effort should be made in an adolescent or young adult to preserve the fallopian tube, if possible.

β-hCG: Typically, β-hCG levels will double every 2 days in a normal first-trimester intrauterine gestation. Only 15% of normal pregnancies will fail to have this appropriate increase in β-hCG levels. The smallest increase over 48 hours that can still be associated with a continuing intrauterine pregnancy is 53%.¹⁰ If β-hCG measurements are unchanged or increasing abnormally, the pregnancy is nonviable, regardless of location. Pregnancies that have inappropriately low β-hCG levels are more likely to be ectopic. Serial β-hCG measurements can be extremely helpful in determining the fate of these pregnancies.

Ultrasonography: Ultrasound studies at appropriate β-hCG levels are usually diagnostic, and often the definitive method of pregnancy dating and localization. Transvaginal ultrasound is highly accurate at identifying ectopic pregnancy, with sensitivities and specificities ranging from 87% to 99%.¹¹ This may require more than one assessment depending on the clinical picture. There is still debate over what β-hCG cutoff should be used as the discriminatory level (the lowest concentration of β-hCG that is associated with a visible normal intrauterine gestation), but this level is generally considered to be above 1,500 to 2,000 IU/L when using a transvaginal ultrasound probe. Above this level of serum β-hCG, a normal intrauterine gestational sac should be seen.¹² Although an intrauterine pregnancy may be detected at lower levels, the possibility that the pregnancy in question is intrauterine cannot be excluded until the β-hCG levels reach the discriminatory range. If no intrauterine gestation is seen, then an ectopic pregnancy should be strongly suspected. If transabdominal scanning is the only method available, the β-hCG cutoff should be 6,500 IU/L.¹³

Declining β-hCG levels: If the β-hCG levels are declining by 50% to 66% every 3 days, it is likely that the patient has experienced a complete resolution of the pregnancy. The β-hCG levels must be followed up until they are undetectable (based on local laboratory values).

Increasing β-hCG levels: If the β-hCG levels are increasing by at least 66% every 2 to 3 days, they should be followed up in a mildly symptomatic patient until they reach the discriminatory zone and the diagnosis can be made ultrasonographically. If the patient becomes increasingly symptomatic before reaching the discriminatory zone, laparoscopic investigation may be considered. It is useful to discuss with the patient whether the pregnancy is wanted. A dilation and curettage (D&C) can be performed at the time of laparoscopy if the pregnancy is discovered to be intrauterine. If the pregnancy is wanted, consider delaying insertion of the uterine manipulator until an ectopic gestation is confirmed.

Abnormally changing β-hCG levels: If the β-hCG levels are declining or rising at an inappropriate rate, the pregnancy (either intrauterine or ectopic) is likely nonviable. However, this does not differentiate between a miscarriage and an ectopic pregnancy.