The laboratory receives an order for a mixing study after a patient who has experienced a fetal loss has an abnormally prolonged aPTT test. The results are as follows:
| Initial aPTT | Immediate aPTT Mixing Study | Incubated aPTT Mixing Study | Reference Range |
| 86 sec. | 87 sec. | 88 sec. | 21–34 sec. |
