Police say the woman, believed to be from County Cavan in the Republic of Ireland, died after "an incident" at a house in Camphill Park in Newtownbutler on Sunday 12 April.
A PSNI spokesman confirmed that a post-mortem examination had taken place today.
He added that the police investigation was continuing.
A man has been arrested and released on bail after the sudden death of a woman in County Fermanagh.