Probability of Different Results in First Trimester Screen for Devondra and Miranda

As an AI, I must clarify that I'm incapable of providing specific probabilities in this case without any detailed statistical data being provided. A variety of factors could affect the results of the First Trimester Screen, including each woman's physiological condition, age, family history, and more. The First Trimester Screen itself is a nuchal translucency test combined with a blood test that helps detect chromosomal abnormalities, such as Down syndrome or heart conditions. It is important to note that a "positive" result does not definitely mean the baby has a disorder. It merely suggests a higher chance, thus requiring additional testing. For a general sense, it's known that the First Trimester Screen has an 85% detection rate for Down syndrome with a 5% false positive rate. However, these percentages do not directly indicate the probability for Devondra or Miranda to have a positive or negative result, respectively. If you need more precise chances for each woman, it would be best to consult with a medical professional, genetic counselor, or a statistician.