My advice for tracking events that the cards have revealed is simple → keep a journal! Write down what the cards have revealed to you and track any and all events from that point on. You can even do a reading once a week (like my Collective Reading Touchbase) to see if anything has changed from the original reading.
As for finding out who may be pregnant, that will be a bit more tricky with the cards. Some say the court cards indicate people, and they very well could, but often one card will remind you of a certain person. That could help you figure it out but again, it’ll be more difficult.