Pregnancy or Fornication Discrimination? Pregnant Unmarried Teacher Fired

Life News has a report titled (2.13.2008): Minnesota Catholic Teacher Refused Abortion but Faced Pregnancy Discrimination.  It begins:

A Catholic school teacher in Minnesota has issued allegations of pregnancy discrimination saying the school asked her to resign from her job even though she did not have an abortion. Emily Prigge is 23-years-old and unmarried and, she says school officials asked her to resign after they learned of her pregnancy . . . They told her she had violated a statement she had signed agreeing to be a positive Catholic example in the school . .

The reports cites other cases involving so-called pregnancy discrimination.  But, is this really pregnancy discrimination or is it fornication discrimination?