i suggest you to dicuss this issue with your wife privately. concidering take it up to the court? don't even think about it. its costly, its time consumng, and you can't win.
even if you have this child without your wife consent (i.e. you win the legal case), how can you get along with her and your child in the future? it seems like a lose lose situation.
the key is to love her but not to push her, let her feel that 3 people under one roof is better than two, let her love you and eventually listen to you...
About 10 years ago, in 1991, a guy called Jean-guy Tremblay made her girlfriend,Chantal Daigle, pregnant and wanted to have the baby. They even went to the Super Court but, in the end, the judge said she was right and could make her decision although she even went to USA for the abortion.