Village growth out of control (villagers breeding too fast)

Village growth is completely out of control. There are around 30 beds and profession blocks in the village but probably well over 200 villagers, possibly 400 as some small houses have 40+ in one room, overlaying each other. What's more is they're still breeding very fast and I don't know how to stop them.

This is on our 3 player MS Realms server - game is so laggy it is now completely unplayable on all devices as soon as the village chunk loads on Android / Win10 and Xbox One S. 3-5sec delay between pressing any button and it reacting, even just to open the inventory, so iron door buttons are completely unusable. 

Standard survival - no experimental updates and we started this as a new server after the Village and Pillage update caused our previous Realm to glitch out completely.

This is for a Bedrock (1.11.4) Realm, affects Android, Xbox and Windows10. The Realm runs perfect when you get out of the village chunk, even in other smaller villages. I even tried downloading and running the game locally on a decent spec i7 desktop and that struggles - almost no difference for myself or anybody else on that world.

I don't think this is a performance bug - it is a village AI bug that means they're not detecting that there are enough Villagers for the number of doors / beds / workstations in the village and deciding to produce more and more.