Cathrina Ann Cahill will be sentenced in November

An Irish woman has pleaded guilty to the manslaughter of her fiance in Sydney last February.

27 year old Cathrina Ann Cahill from Wexford is accused of stabbing 29 year old David Walsh in the neck after a fight outside their home in Padstow.

The court in Sydney heard that the relationship had been abusive and Ms Cahill may have been suffering from post traumatic stress at the time.

She was originally charged with murder but has pleaded guilty to the lesser charge of manslaughter.

The sentencing hearing is due to start on November 1.