Es un disfenismo, una expresion, algo ofensiva, para demostrar "asombro". In english a similar dysphemism would be "holy shit".

Hi, I also understand that phrase as an insult, but I think you shouldn't use it against yourself because is a pejorative phrase. Instead you can use it against other people when they act as idiots and tell them: " La madre que te parió" Though it's not a completely strong insult, it express your discomfort Hope that helps!

Aquí en Argentina se usa como insulto. Por ejemplo: Si te golpeas dices: La que me pario.