Grenoble revealed on Tuesday that the incident happened last week at the Top 14 club’s training centre and the 20-year-old was taken to hospital.
There are reports that the loose forward became dizzy while in his room.
Berruyer won the World Rugby U20 Championship with France last year, defeating England 33-25 in the final.
In a statement the club said “Antonin Berruyer had a stroke last week. This accident happened at night in his room at the training centre. Antonin was immediately taken care of and hospitalised at Grenoble University Hospital. He underwent appropriate treatment and, after a period of observation, was able to return home this weekend.
“Antonin was again at the hospital on late Monday afternoon to pass tests that confirmed that the problem had been perfectly addressed.
“Antonin returned home, as a family, to rest. He will be off until the end of the season.
“The whole of the FCG thinks very strongly of him and wishes him a quick recovery.
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