Turning over onto tummy in cot/moses basket 20 weeks old

[melc78]

Hi, I have an almost 20 week old, that was a brilliant sleeper until the last few nights. He has started to turn over now in his sleep onto his tummy. I have moved him from his moses basket into a cot, as I thought maybe he needed more room to move. I have nothing in the cot, except a brand new firm mattress, with a waterproof case and a fitted sheet over it. Having seen him turn over several times and lay face down onto the mattress I am really worried about SIDS. He is always laid down on his back, is 100% breastfed, the cot (and previously the moses basket) is right next to my bed, and neither myself or hubby smoke.
Can anyone offer any advice, as I am going out of my mind worrying about him all night long and getting very little sleep as a result?

Once he masters turning back again this will no longer be a problem but I remember seeing some sort of fitted sheet for the cot with a central attachment/material "arms" that sort of velcro around baby's waist to hold them in the middle of the cot and stop rolling. Not sure if that would be worth a look?

Can't find the damn thing online now though. A search on mumsnet might reveal it again though- I'm pretty sure it was on the sleep board in the last few weeks...

In the meantime remove all extras from the cot, maybe fashion wedges with rolled up pillow cases to stick either side of him under fitted sheet so he can't physically roll over them and they act as barriers IYSWIM?

You could invest in a movement monitor to give you peace of mind?

Thank you. I did buy a movement sensor, although it was second hand, (Angelcare AC401) but cannot get the sensor pad to work. Also have a video monitor which eases my mind while we are up. Going to order a new sensor pad now see if that helps, as everything else works. I guess once he is able to turn himself over and able to crawl it may be less of a worry.