The role of the history and physical examination in the diagnostic evaluation of patients presenting with symptoms of ectopic pregnancy has become less defined with the use of other modalities such as ultrasonography, quantitative β human chorionic gonadotropin (β-hCG) and progesterone assays, laparoscopy and endometrial sampling. Yet each of these testing modalities has limitations. Identifying reliable findings from the history or physical examination would help increase the specificity and sensitivity of diagnostic studies. Dart and associates conducted a prospective study of patients presenting to an emergency department with abdominal pain or bleeding during the first trimester to identify historical or clinical findings that may predict ectopic pregnancy.

Of the 438 patients in the study, 57 (13 percent) were found to have an ectopic pregnancy. Of the remaining patients, 214 had a normal intrauterine pregnancy, and 167 had an abnormal intrauterine pregnancy.

Analysis of the data revealed three groups with a less than 10 percent frequency of ectopic pregnancy. The first of these groups included patients with no pain or only mild pain and no risk factors for ectopic pregnancy. In this group, 10 of 182 (5.5 percent) patients had ectopic pregnancy. The second group included patients with moderate to severe pain but no cervical motion tenderness, peritoneal signs or risk factors; ectopic pregnancy was diagnosed in 10 of 115 (8.5 percent) patients with these findings. The third group included patients with moderate to severe pain and cervical motion tenderness but an open cervical os. No case of ectopic pregnancy was found in the five patients with these clinical findings. The remaining 52 patients did not fit into any of these groups and had a high incidence (23 patients, 44 percent) of ectopic pregnancy.

Patients with ectopic pregnancy were more likely to have moderate to severe, sharp pain, lateral or bilateral tenderness on abdominal or pelvic examination, a uterus smaller than eight weeks in size, and cervical motion tenderness. Peritoneal signs, although not common, were highly predictive of ectopic pregnancy. Risk factors found to be predictive of ectopic pregnancy included a history of infertility or use of an intrauterine device, a prior tubal ligation and pelvic surgery.

Neither tachycardia nor hypertension were predictive of ectopic pregnancy. Other findings that were not predictive of ectopic pregnancy included the presence of an adnexal mass, a history of ectopic pregnancy, a history of pelvic inflammatory disease, the amount of vaginal bleeding and an open cervical os.

The authors conclude that although predictive variables can be identified, clinicians cannot reliably exclude ectopic pregnancy on the basis of the history and physical examination findings alone. The authors state that one possible role for the history and physical examination is to determine the need for emergency ultrasonography at hospitals where this study is not readily available at any hour. The need for additional emergent diagnostic testing to identify ectopic pregnancy may be determined by the presence or absence of risk factors.

editor's note: The diagnosis of ectopic pregnancy is not straightforward. Serial quantitative β-hCG determinations are enhanced by the clinical examination, although a 48-hour interval is required between measurements. Abdominal or transvaginal ultrasonography is useful in identifying whether the pregnancy is intrauterine or ectopic. Reassurance must be provided to the anxious patient during evaluation, and a specific diagnostic protocol is useful in providing absolute reassurance that the pregnancy is viable.—r.s.