They've been stirring up plenty of trouble on Teen Mom ever since the show began.

So it was no surprise to see Farrah Abraham and Amber Portwood come to blows during the Teen Mom OG reunion on Monday.

Amber stormed on stage to confront the 25-year-old for making comments about her fiance looking like a 'pedophile', and even took a swing at her co-star.

Coming to blows: Amber Portwood and Farrah Abraham fought during the Teen Mom OG reunion on Monday evening

'Just because somebody's 20 years older than you doesn't mean he's a f***ing pedophile,' she shouted.

'Shut your f***ing mouth, do you understand me? I'm going to stand up for my f***ing man!'

While most of Amber's foul-mouthed tirade had to be bleeped out, she was also heard yelling: 'You talk a lot of s**t with people all-round, don't you? Watch your f***ing mouth.'

Getting physical: Amber even tried to slap Farrah - but fortunately missed

Confrontation: Amber stormed on stage to confront Farrah for making comments about her fiance looking like a 'pedophile'

'Shut your f***ing mouth': Amber unleashed a foul-mouthed tirade against her co-star

Farrah stayed rather calm, even when the 26-year-old then tried to slap her - and fortunately missed, as Dr. Drew Pinsky and a producer tried to hold Amber back.

Amber was later removed from the stage while she screamed at Farrah: 'Shut your f***ing crooked lips up!'

It all began when Dr. Drew brought up the fact that Farrah's boyfriend Simon Saran had allegedly called Matt a pedophile off camera, because he's two decades older than Amber.

Not holding back: Most of the insults she threw Farrah's way had to be bleeped out

Quite the insult: Amber was later removed from the stage while she screamed at Farrah: 'Shut your f***ing crooked lips up!'

Causing trouble: It all began when Dr. Drew brought up the fact that Farrah's boyfriend Simon Saran had allegedly called Matt a pedophile, because he's 20 years older than Amber

Simon insisted that he had just been joking, but Amber stormed on stage after Farrah said: 'Well, I'm sorry that Matt probably looks like it.'

But things got even more physical when Amber's fiance Matt Baier pushed Farrah's father to the floor.

Farrah responded by branding Amber and Matt 'criminals', before the couple were removed from the set.

Uh oh: Things got even more physical when Amber's fiance Matt Baier pushed Farrah's father to the floor

Keeping her cool: Farrah remained calm, even when Amber tried to slap her

Take them away!: She called the couple 'criminals' as they were removed from the stage

Earlier in the show, Maci Bookout had revealed that she fell pregnant with her third child while on birth control.

She also shared an emotional moment with Ryan Edwards, who is the father of her eldest child, seven-year-old Bentley.

The show ended with Maci, Amber and Catelynn Lowell on stage together and complaining about Farrah, before the three of them removed their microphones and walked away.

That's better: Amber was a lot more calm while chatting to Dr. Drew Pinsky alone

The ex factor: Maci Bookout shared an emotional moment with Ryan Edwards, the father of her eldest child, and also revealed that she got pregnant with her third child while on birth control