Why do my outlets keep going out?

My husband and I recently bought a 1983 house. Before closing, one of the things that we had the previous owners fix was gfci outlets in all wet areas due to the house not having any. During our final walk through we noticed that they had put in gfci breakers on every breaker in the box and not outlets. We had them come back in and put in the outlets.

Now to the problem… About a month after closing we noticed that one of the breakers was tripped that had a new gfci outlet installed (in the bathroom). It then happened a couple of more times to just that one bathroom. Recently, the problem has become wide spread. Every bathroom (we have 3) breaker that has a gfci outlet installed has been tripping and shutting off power to all outlets and light switches on that breaker. It has now happened twice with all bathrooms.

I am concerned about safety. Also, why would this be happening? It is important to note that this is ONLY happening to breakers with the new gfci outlets installed.

Thanks in advance!