Your stats are wrong and overstate the figure by about 92%. The figure given by Theresa May on 22 February 2017 was 25,000 but the actual number was about 26,000 between 2003/04 and 2009/10.
https://www.statista.com/statistics/473264/number-of-hospital-beds-in-the-united-kingdom-uk/
That doesn't give any numbers other than to say that the number reduced by over 70 thousand beds in the UK NHS in the 10 years before 2009 and doesn't give any source for the numbers. According to FullFact, a UK based independent charity checking a variety of facts, the numbers are as I gave (
https://fullfact.org/health/number-hospital-beds-falling/). Their numbers are sourced from the NHS themselves and should therefore be accurate. They even quote Theresa May as giving those numbers, giving a link to the live TV feed of her saying this at Prime Minister's Questions! The only difference seems to be that your source talks about UK beds and mine about English beds, perhaps the other 24 thousand were in Scotland, Wales and Northern Ireland but that doesn't seem likely as Scotland only had 13,246 in 2017/18. According to the same site the basis of collection of the data changed in 2010 so the numbers are not comparable. Even the American website you are using notes that there was a break in reporting in 2010.
Sorry but I don't accept your original claim of over 50 thousand hospital beds lost under Labour in a 10 year period. The total number of overnight hospital beds in the English NHS has actually been falling almost constantly since the 1980s. This means that hospital beds have been reduced under both Labour and Conservative governments, in response to declining lengths of stay.