porca madonna

Way to insult Virgin Mary. Italians use it when they are very angry or feel hard pain.
Similar expressions connected to the Virgin Mary are "Madonna Bocchinara", "Madonna Puttana".
Italian creativity is often shown in the creation of similar expressions.

Big insult to divinity, in paticular to Maria, the mother of Jesus.

It's something very offensive for Christians, it's lime swearing vs the mother of Jesus. In Italy people uses to say that when they are very very angry