Please read the instructions on the last page about how to do pelvic floor strengthening exercises. Basically, you aim to have a difference of 3-4 numbers higher when you contract your muscles on the manometer, which will probably be starting at 2. I'm assuming you know that there is NO connection between the stretching of the perineum and the pelvic floor exercise with the manometer. The manometer only relates to pelvic floor not to stretching before birth.