The man in his 30s, who can not be named by The Courier as it would identify the victim, pleaded guilty in the Ballarat Magistrates Court to aggravated assault and threats to kill.

The court heard on Saturday at around 5.30pm, the man met the victim outside a Doveton Street business to collect his children, in order for him to spend Father's Day with the children.

The victim and the guilty man argued about where the man would be staying with their children over the weekend. The court heard there were no defined custody arrangements for the family.

Police prosecutor Leading Senior Constable Clint Prebble said the man then "struck the victim in the lower back" with a bag, before putting her in a headlock.

"The accused threatened her by saying, 'I'll f**king kill you, I don't care if I go to jail for it'," the prosecutor said.

After she tried to push the man in his 30s away, the victim ended up on the ground, and she was struck to her head and shoulders by the accused.

Senior Constable Prebble said three witnesses saw the incident take place, and the victim reported "soreness in the back, neck and abdomen".

When interviewed by police on Sunday, the man made partial admissions to the offending, saying that he did get into a dispute with his ex-partner but did not remember exactly what he said.

The court heard the man had previously been convicted of threatening to inflict serious injury in a family violence context.

The man's defence lawyer Gemma McInerney said the dispute occurred in a "heightened context" after a dispute over child arrangements, but her client had "expressed remorse for the physical violence".

She said the man did not know the victim was pregnant until he was told by police on September 1, and he had been in custody for two days.

Ms McInerney said the man is recently in a new relationship, which spurred the dispute, and his previous family violence offences which occurred with the same victim had happened as their relationship broke down.

She also told the court the man had previously completed community corrections order and has stable accommodation and work.

Magistrate John Murphy told the court that more than "one woman per week is killed in Australia through domestic violence", and said that men needed to respect women.

"Every day of the week I deal with it, I travel a round a lot (as a Magistrate), from Shepparton to Wodonga ... it's just non-stop," he said of family violence cases.

He said that a Corrections Victoria report stated "he's a low risk of reoffending, but you look at his priors" and it did not add up.

The man was sentenced to a community corrections order and 100 hours of community work.

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