Boss can let any body leave at ant time, it's at will, as long as the the boss treats everyone the same way. If she was the only person let go, everybody else is still there, that might be different story.
Can she prove that she was fired after the proffesor found out she was pregnant? If not, she has no case
Can she prove that she was fired after the proffesor found out she was pregnant? If not, she has no case