Dreigende miskraam in de eerste lijn: Diagnostische waarde van anamnese en lichamelijk onderzoek

Aim Ultrasonography is the gold standard for establishing a diagnosis in first-trimester vaginal bleeding. We studied the diagnostic value of anamnesis and physical examination in first-trimester bleeding. Methods We conducted a prospective population-based cohort study in 74 general practices in Amsterdam involving 225 patients with first-trimester vaginal bleeding who had been referred for an early pregnancy assessment. The data of 204 patients were analysed. Two diagnostic models were constructed based on symptoms and the results of gynaecological examination to identify diagnostic subgroups relevant to clinical practice. Results Model 1 increased pre-test probability of viability from 47% to a post-test probability of 70%. Model 2 resulted in a post-test probability of 41% of complete miscarriage, given a pre-test sample probability of 25%. The tentative diagnosis of a general practitioner, based entirely on clinical judgement, turned out to be a poor predictor of the diagnosis confirmed by ultrasonograph (pre-test probability of 47% changed to a post-test probability of 58%). Conclusion In first-trimester bleeding neither statistical prediction models based on signs and symptoms nor clinical judgement are valid substitutes for ultrasonograph assessment in establishing a diagnosis.