In the movie The Talented Mr.Ripley, was there any conclusive evidence in the film if the pregnant girl was murdered or was it simply a suicide. If she was pregnant, was there no way to know who the father was?
The Italian girl drowned herself/committed suicide following Dickie's rejection of her, as it would have been a humiliating and unbearable situation to be an unmarried mother in Italy in the 1950s.
I could be wrong but I don't think it was ever suggested that it was murder, in either the film or the book.
I think it was quite clear that Dickie was the father but he wanted nothing to do with it, as it would upset his comfortable life. So I don't see that as an issue, and as you point out in your comment, it would have been pretty hard to ascertain that then anyway.