Pregnant woman jailed over car crash that killed her friend

A heavily pregnant young Victorian woman will give birth in custody after killing her friend in a high-speed accident.

On New Year's Eve 2015, 18-year-old learner driver Gemma Sargent drove her four young friends from Ballarat to Geelong, without a licensed driver supervising her.

Police has already warned her twice not to drive unsupervised - including just two days before the accident.

The County Court of Victoria was told on Monday that during the trip, Sargent overtook another car that was driving at 130km/h.

She hit the road's gravel shoulder, overcorrected twice and lost control at speeds possibly up to 140km/h.

Her Holden sedan skidded before impacting into a "mound of dirt and rocks" and flipping multiple times.

Passenger Nathaniel Merritt-Price died of severe head injuries at the scene, while another passenger Jolene Bounday had two fractured vertebrae, a head wound, and other injuries.

Judge James Montgomery said Sargent, now 20, had been "showing off", attempting a manoeuvre an experienced driver never would have tried.

"You grossly overestimated your abilities as a driver. There was no need for you to pass a car that was itself driving 30km/h over the speed limit," he said.

During her trial, the court was told Sargent's passengers thought they were driving too fast and wanted to slow down.

"Stop the car, I want to get out, I don't want to die tonight," Mr Merritt-Price had asked her, according to Ms Bounday.

Mr Merritt-Price's father's victim impact statement revealed his "family has changed forever".

"I want to place on record the despair that is part of me every day," he said in his statement.

Sargent, who had her first child during her mid-teens, is being held in custody in a mothers' inmate unit, where she will be allowed to care for her new baby for several years.

She was jailed for eight years for culpable driving causing death and negligent driving causing serious injury, and must serve a minimum of five years before being eligible for parole.