A pregnant Army vet, Liv Abreu, was harmed Tuesday when her Bronx sweetheart stabbed her a few times in the stomach, killing her unborn baby, police say.

The couple was alone in their apartment on Walton Avenue close East 165th Street in West Concourse, and around 12:30 a.m. that’s when the night took a turn for the worst.

The crazed beau, whom police sources recognized as Oscar Alvarez, cut the eager mother — who was in the last trimester of her pregnancy — no less than six times in the middle, police said. Alvarez at that point supposedly fled in Abreu’s 2004 Jeep SUV.

A bleeding Abreu faltered into a neighbor’s condo, where she called 911, police said. She was raced to Lincoln Hospital in basic condition and taken into medical procedure. The unborn child was articulated dead.

Cops later discovered Abreu’s car deserted in the street. Almost four hours after the cutting, Alvarez handed himself over to police, specialists said. He was arrested with charges pending.

“I heard a scream but it didn’t register because they always argue,” said a neighbor, who requested to stay mysterious. “That’s just a shame,” she added. “I just feel sorry for her … and the baby.”

It was not clear what incited the assault, or if the man was the infant’s dad.

In February, Abreu — who distinguishes herself as a US Army Combat Veteran — presented on Instagram a sonogram photo of her unborn infant with the caption, “My little human.”

She kept on chronicling her pregnancy on the online networking website. Most as of late, in April, she posted a sonogram endearing the baby’s face.