17 week old waking every 40 mins at night

[Samum123]

My 17 week old isn't the best at getting to sleep but once he is he normally sleeps well. Recently he's been going to sleep for a good stretch (8pm - 3am) last night, then waking up every 40 - 50 minutes after that until it's time to get up.

He doesn't seem hungry when he wakes up, so I'm not feeding him as don't want him to eat if he doesn't need to.

He is still swaddled (arms only), and this is fine for the first stretch, but by the time he's woken up the first time he's got his arms out, I then re-swaddle him and shush him back to sleep, but 40 mins later he's broken free again and woken up and so the cycle starts. He wakes himself up by waving his arms around so a sleeping bag doesn't seem the best option yet.

He's definitely starting to teeth as is dribbling a lot, and chewing his hands a lot, but isn't distressed when he wakes so I'm assuming it's not that.

So, should I...
A) try feeding him and see if he sleeps more deeply after?
B) swaddle him until he wakes up then try something different?
C) sleep train?
D) a combination of the above?

Please help, I'm exhausted as when he wakes up the first time I don't really get to sleep again. Thank you in advance.

If baby is waking up within an hour of last wake up, I wouldn't resettle, if feed.

I say that on the basis that one wake up and needing a resettle could be any number of reasons for waking. But if baby is waking again so soon, it suggest a that whatever 'need' baby has wasn't met last time. So if you just do the same thing, you'll get the same result (waking again soon after the resettle). So I'd do something different and the first option after resetting would be a feed.

If baby likes the swaddle and you are happy to keep It, how about investing in something more in-escapable? You can get swaddles you zip baby into. Or alternatively you could use a normal sleeping bag with the arms holes sewn up.

Daytime naps can also affect night time wake ups. A baby getting lots of daytime sleep is likely to wake less frequently when asleep. So keeping naps frequent helps.

There's also a thing called 'calorie loading', which means getting as much of baby's calorie need into baby during the daytime, so that less is needed at night. So bigger, more frequent daytime feeds.