Ireland lost control of the U20 Six Nations when slipping to a narrow 19-14 defeat to England at Donnybrook.
This means the Irish are now joined by England on two wins out of three.
They should have been further than 9-6 clear at the break from three Ross Byrne penalties.
On resumption, England replacement Piers O'Conor made an immediate impact, fielding Byrne's kick and taking it home.
The Irish responded with a sublime try manufactured by Byrne and Ringrose, finished by Fitzgerald for 14-11 in the 54th minute. From there, the visitors set-piece began to dominate and reduce Ireland's attacking options.
Their scrum-half James Mitchell kicked his third penalty and centre Joe Marchant slid inside for the killer try in the 71st minute.