Mosen, 27, was sentenced to prison for attempting to procure an abortion by unlawful means. He faced two other charges, both for earlier assaults on Miss Te Huia and was sentenced to a year's prison for each of them, to be served at the same time as the three-year term.
He was already in prison, serving two years for growing and supplying cannabis and cannabis oil, and supplying methamphetamine. The three years will be added to those two.
Justice Williams said it was unusual to allow a victim to read their statement in court.
Miss Te Huia said Mosen was "cool" at the start of their relationship, but soon became violent.
"He hit me all the time. I would try to leave and he wouldn't let me. He threatened to kill himself if I didn't go back."
When he "tried to murder" her baby for the first time he cried afterward and said he was sorry, she said. The second time, four days later, she reached the breaking point, asked for help and left him.
She still had nightmares about what Mosen put her through, and believed that was why her baby sometimes woke up screaming rather than crying.
Their relationship began around October 2011, and Miss Te Huia fell pregnant in March 2012, Justice Williams said.
In April 2012, when she wanted to leave, he threw a shovel at her, hitting her legs and causing swelling and bruising.
In June he tried twice to abort the baby. The worst incident on June 8 when he dragged her on to a bed by her hair and punched her in the stomach with full force, saying: "I hope that's done it".
She crouched, winded, to protect the baby and herself, then called for help, escaped and went to Wanganui Hospital.
Mosen had asked for his identity to remain suppressed. His lawyer, Roger Crowley, told Justice Williams so, but did not push for it.
His client was remorseful, he said. Mosen had written to the judge to say he was sorry, not a violent guy and wished he could change things.
Justice Williams was willing to accept that, but said Mosen had admitted the three charges and had to be sentenced accordingly.
He also made an order protecting Miss Te Huia from him in future.
