Hi. If it is actually the generic form of the pill it should be exactly the same as the original.
If you have an old packet left around you could look at the amounts and types of each hormone to compare.
I had a quick look and I can't tell because there are so many different types of
Ortho-Novum... eg
Ortho-Novum 7/7/7,
Ortho-Novum 1/35, etc
If you were taking
Ortho-Novum 1/35 prior to Nortrel 1/35 they are the same thing.