Why is there no "Loss" option?

Why do no period trackers (that I have found yet) include pregnancy loss? Even the apps that include "Did you take a test?" (Followed by the options) "Yes I am pregnant!" Or "No go back", I feel like tracking when the loss occurs is important information to keep for later just like when I'm cramping or feeling emotionally unstable, have others found this an issue? (I mostly just had to write it in the commonly found "Notes" section.)