After the drawn Test match at Wormsley, the ODI win gives Australia a 4-2 lead, and means they need only two wins from the remaining five limited-overs contests in order to retain the Ashes.
The new points system for the Women's Ashes - which awards six points for a test and two for each limited overs contest - has been introduced this summer and welcomed by the players.
England captain Charlotte Edwards told Sky Sports: "It was what our Ashes series needed. It preserves Test cricket, which is the most important thing, but equally we get to play the more popular formats which are one day and Twenty20 which the media and the public has a huge demand for."
The three formats are making the Ashes more competitive, something wicket-keeper Sarah Taylor says can only be good for the game.
"It makes each and every individual game massive for us and with Australia holding the Ashes it is nice to know they can't come out here and just draw a Test match and retain them," she said.
"They have to win it as much as we do."
The success of this new format, introduced by the England and Wales Cricket Board, could lead to changes in the men's and women's game on a global scale.
With Test cricket attendances low in many parts of the world, the format preserves the oldest form of the game, whilst also adding importance to the more popular limited-over contests.
"I think there is definitely scope for it [to be used elsewhere], says Sarah Taylor.
"For a series involving only two or three Test matches then maybe they can include it. I guess we are the guinea pigs in that respect, but we are enjoying it and like the fact it is about this series."
Charlotte Edwards agrees, and says the three-format approach could also boost Test cricket in the women's game.
"Hopefully other countries across the world will look at this format and want to take it on board and want to play Test cricket," she said.
"It's important Test cricket is alive in women's cricket. I think there is so much we can learn from Test cricket and there is a huge passion from the players for Test cricket."
The final two T20 internationals, at Southampton and Chester-le-Street, will be played before the men's T20 internationals between England and Australia.
Check out the video on this page to hear more from Charlotte and Sarah on this topic - and their thoughts on the artwork the team produced of each other for Cricket United.