Why is it a social custom to say "congratulations" to a guy when his wife/gf has had/is having a baby?
What has he done to deserve the sentiments? All he's done is have an orgasm and spurt some semen into her? So what's so special about that?
Meanwhile it's the woman's body that is carrying and nurturing the baby. It's she who has to go through childbirth, a process that changes her body forever. If anyone deserves to be congratulated, it's her.
Don't take me wrong, I'm not male-bashing here (I love men) but just trying to make sense of this world we live in.