Ottavio Gadaleta, 29, attacked one of the women, leaving her with a fractured ankle, knocked another unconscious and pushed the pregnant woman, after attending a birthday party in Scarborough in the early hours of August 2, last year.
York Crown Court heard how Gadaleta had drunk a substantial amount of alcohol and had become angry when his partner at the time had asked him to wait when he wanted to speak to her.
He left the party, but then returned 10 minutes later and an argument followed between Gadaleta and his partner, in which he used a number of derogatory terms to describe her.
Two of the woman's friends tried to intervene and that is when Gadaleta pushed one of them - who was in the early stages of pregnancy - at the time, and then knocked another out of the way.
Prosecuting Jon Harley said: "He hit the second complainant and she went flying backwards on the pavement and hit her head on the curb.
"His partner shouted at him to calm down and he then punched her in the right eye, before she punched him to the left side of his face.
"He lost control, grabbed her by the arm and shook her violently before throwing her sideways. As she landed, her ankle buckled underneath her and she felt an intense pain."
In victim impact statements read out to the court all three women said that night had a detrimental impact on their mental health.
Gadaleta's partner, who was a care worker and had sent her own children to live with their grandparents during lockdown to protect them, was not able to do all the activities she had planned with them in the summer due to her fractured ankle.
Gadaleta, of New Queen Street, Scarborough, pleaded guilty to causing grievous bodily harm, assault occasioning actual bodily harm and common assault at a previous court hearing.
In mitigation, Gadaleta expressed his remorse for his actions that night, stating it was out of character and that he had drunk too much alcohol that evening.
Sentencing Gadaleta to 12 months in prison, the Recorder of York, Judge Sean Morris said: "Because of your actions that day, two women ended up in hospital - one having her leg in plaster for a fracture and another, rendered unconscious, losing her vision on eye, which thankfully came back.
"You behaved disgracefully and attacked three women. One, as I say was pushed and cracked her head on the road, the other one you threw to the ground and she fractured her ankle.
"These offences are so serious that only an immediate custodial sentence can rectify the gravity of this."