Catholic priests and nuns

My ancestors lived in the Natzungen/Frohnhausen and Spellen areas of Westphalia. I am tracing the 1700's and early 1800's at this time. They were members of the Catholic Church. There are a few children that I have found no record of (other than their birth/christening records) and am wondering if perhaps they became priests or nuns. Can anyone tell me if there is a way to search for names and dates of persons that may have entered the priesthood or joined a religious order during this timeframe?

Thank you for any assistance in this search.

Regards, Kathy Montelaro