A woman pregnant with twins has been arrested and accused of fatally stabbing her boyfriend after they fought in her Washington Heights apartment early yesterday morning. Kelly Lopez-Roldan, 22, was arrested for the murder of 24-year-old Antoine Scott. He was found with stab wounds to his chest shortly before 2:30 a.m. at 450 W. 164th Street. And sources tell the Post that Lopez-Roldan plans to argue she committed the act in self-defense.

Scott allegedly let himself into Lopez-Roldan's apartment Wednesday morning with a spare key, and started punching her in the face. A police source told the Post that Lopez-Roldan managed to break away and grab a kitchen knife, which she plunged twice into Scott’s chest. “There was blood everywhere. It looked like he was running around for a while,” the source told them. Roldan’s 4-year-old son by another man was also sitting on the bed at the time.

Despite the fact the couple already had one child and Lopez-Roldan was four months pregnant with their twins, the two were living separately. Police said they had a volatile relationship, including past incidents involving police and claims of domestic violence. “The couple was always fighting, about three times a week,” Anthony Rodriguez, the building’s custodian, told The Uptowner. “From what I hear, there have been noise complaints about the couple.”