John White held a Stanley knife to his girlfriend's back, and stood behind the door, when her worried mother called to see if she was all right, on January 31, said prosecutor Robert Sandford.
Afterwards, White accused her of gesturing to her mother and stabbed her in the legs, before smashing the knife handle over the back of her head, causing blood to pour from her scalp.
Two days later, when she revealed she was pregnant, White spat on her and threatened to harm the baby.
The woman went outside to where her mother was waiting in a car, and the police were informed.
The court heard their relationship began in July 2019, but White began demonstrating "controlling and coercive" behaviour in October, after her grandmother's funeral.
Several weeks later he accused her of sleeping with a neighbour and punched her, leaving her with a black eye and a bloody nose.
He called her names and blamed her for everything, before confiscating her mobile phone and checking her text and Facebook messages. He took control of her bank account, banned her from contacting her family and even forced her to give up her job.
He kicked, punched, bit and slapped her, and even broke her glasses so she couldn't see properly.
In a statement, White's victim said she was "lucky to be alive" after her ordeal, but still suffers flashbacks.
"At the moment I don't feel as if I will ever be safe again," she said.
On Wednesday, the court heard White was sentenced to eight years in prison for wounding with intent and attempted robbery, and was convicted of dangerous driving in 2018.
Ian West, mitigating, said: "To his credit he readily accepts it was entirely his fault. Had it not been for his drink and drug problems this had all the makings of a successful relationship."
White, 27, currently of HMP Doncaster, pleaded guilty to controlling behaviour and assault occasioning actual bodily harm.
Recorder Jo Kidd jailed him for 38 months and imposed a five year restraining order.