A capillary tube pregnancy test

The experience with a new, simple, and sensitive capillary tube pregnancy test requiring no refrigeration is described. The results of this test and other tests are compared against histologic results. The ½ unit capillary test, defined as having a sensitivity of 0.5 I.U. of HCG per milliliter, had a higher percentage of agreement with histopathologic results (99.65 per cent) than all other tests studied. The false-positive rate was 0.07 per cent and the false-negative rate was 0.28 per cent. In this series of 1,486 tests, 21 cases of pregnancy, identified by a ½ unit test, were missed by one or two unit tests. The earliest detection of pregnancy by the ½ unit capillary test confirmed by histology was 3 weeks from the last menstrual period (four cases).