Marley Wiltshire, who was jailed in 2013 for bounding and raping a woman, left his young victim with a fractured nose, cheekbone and wrist.
Prosecuting at Preston Crown Court, Joe Allman said the woman had begun a relationship with him while he was in prison and it continued when he was released, until September 2020.
When they broke up he called her repeatedly and even turned up at her opticians appointment in Preston.
On the day in question, he banged on her door and climbed in through a window.
Mr Allman said: " She did not immediately make him leave. They talked for half an hour and then for reasons which are unclear he then punched her in the left eye and pulled her hair."
Wiltshire then pulled the woman to the floor and into a bedroom where they sat on the bed while she tried to "diffuse the situation".
He added: " At some point a parcel was delivered, She collected it and took the opportunity to escape through the open front door, however he grabbed her hair and pulled her back inside.
The court heard he punched her repeatedly in the face, dragged her into the living room, and shoved his fingers in her mouth.
The frightened woman screamed and bit him. He then dragged her by her hagir, causing clumps to fall out, and knocked her to the floor.
She was punched to the face again, and when she put her arms up to protect herself he kicked them.
Mr Allman said: "He repeatedly promised to stop but when she lowered her arms he punched her again.
"This went on for a sustained period. Throughout she was continually trying to get away.
"It should be noted she was six weeks pregnant. Mr Wiltshire was aware of this. She tried persuading him to stop by reminding him she was pregnant but to no avail."
The attack stopped when Wiltshire rang his mum's friend and told her: "I'm going back to prison, I've hit her."
The victim's mother arrived at the house after receiving phone calls from Wiltshire's mother, and found blood spatters and clumps of hair on the walls.
She found the woman sitting on the sofa bleeding and apologising for the state of the house and the blood.
She was taken to hospital with extreme bruising around ears, face, jaw and arms, and fractures.
When Wiltshire was arrested in Lostock Hall the following day he told police: " I have hit her, she provoked me. I warned her I have a bad temper.
"I'm not trying to justify my actions.
"I'll take a GBH all day, I've hit her - nothing was intentional."
In a victim statement the woman said she had suffered nerve damage and was having counselling as the incident had enhanced her mental health issues.
Wiltshire was recalled to jail on his licence.
Judge Simon Newell jailed him for 10 and half years and imposed a restraining order.
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