Stephen Cahoon of Harvey Street in Derry admits grabbing and pushing Jean Quigley during a row in July 2008 but denies her murder.
Jean Quigley's mother found her daughter# s naked body lying on a bed at her home in Derry city on July 26th 2008.
The 30-year-old mother of four had known Stephen Cahoon since St. Patrick's Day that year and the jury heard they struck up a “loving relationship” that led to her becoming pregnant with his child soon afterwards.
Cahoon became a suspect after the PSNI learned there had been a falling out between the couple in the lead up to her death.
From the witness box today, the accused admitted they fought on the night in question. He said he saw # red# when she told him the baby wasn# t his.
He said he # snapped# , pushed her onto the bed and put his hand on her throat, but stopped when her face started to turn a different colour.
He said he gave her CPR but it was no use and insists he didn# t know she was dead when he left.
His trial will resume next week.