Valerie Cadogan was cycling with her husband when she struck the 25cm (10in) wide, 11cm (4in) pothole and hit her head, Newport Coroner's Court heard.
Council workers were called to the area within hours to fill in the potholes in April this year and make the area safe.
Coroner David Bowen said the effects of the impact may have been lessened had Mrs Cadogan been wearing a helmet.
Mrs Cadogan was airlifted to Bristol's Frenchay Hospital after the incident but never regained consciousness. She died the following day.
The Newport Coroner's Court hearing was told Monmouthshire council immediately filled the pothole on St Mary's Road.
Mark Watkins, of the local authority's highways department, said the road is inspected annually and they had had no reports of defects there following an inspection in June 2012.

The ruling means that tax subsidies that make health insurance affordable for low-income individuals can continue.
United Health Group was the best performer on the Dow Jones, up 2.7%, while Tenet Healthcare rose 12%.
Overall though, the main US share indexes closed lower.
The Dow Jones closed down 74 points, or 0.4%, at 17,891.90. The S&P 500 fell 6 points, or 0.3% to 2,102.31 and the tech-heavy Nasdaq slipped 10 points, or 0.2% to 5,112.19.
The failure to find an agreement between Greece and its creditors continued to hang over shares.
In economic news, the latest numbers on US consumer spending showed a monthly increase of 0.9%, the biggest gain in six years and accelerating from April's 0.1% rise.
Personal income increased 0.5%, the same as the previous month.
There was a small increase in the number of people claiming jobless benefits, but the underlying trend still shows a tightening labour market.
Oil and gas producer Magnum Hunter Resources shares rose 6% after it said it expected to raise $600-$700m by selling its 45.5% stake in its natural gas gathering subsidiary, Eureka Hunter Holdings. Its shares had fallen some 44% this year on concerns over its liquidity.
Shares in Nasdaq listed Netflix fell 2% on the news that billionaire investor Carl Icahn had sold his remaining stake in the TV and movie subscription service, in part because he is worried that financial markets are "extremely overheated".
A 72-year-old cyclist died after she fell from her bike after hitting a pothole in Monmouth, an inquest heard.
[NEXT_CONCEPT]
(Close): A supreme court ruling that upheld a key part of President Obama's healthcare plan lifted shares in US health companies.