First-time cloth users often wonder if they can just use one-size diapers from birth. After all they are marketed as a "birth-to-potty-training" solution. While they claim to fit from birth though, in my experience very few of them actually do fit from birth. They either look very bulky on and/or do not seal tighly around the legs resulting in pee/poop leaks.
With that in mind, I tried a few OSFM brands on J during the newborn stage to see what the fit was like. (I was using newborn cloth diapers full-time at that stage). Since he was born weighing only 2.2kg, I was lucky to be able to see the fit of these diapers throughout a wide weight range.
This post is quite photo-heavy and I am presenting these in chronological order, ie from lowest weight to highest weight.
*** 3 weeks old, 2.4kg & 50cm ***
J is wearing a Best Bottoms cover here with a small Snappy Nappy insert and much to my surprise we got a snug fit around his little chicken legs and waist using the smallest rise setting and cross-over waist snaps. It was a little bulky, but not too much.
*** 3.5 weeks old, 2.55kg & 50cm ***
Here J is wearing a Charlie Banana OS pocket diaper with the small insert. The fit is quite bulky on him, but there are no leg or waist gaps. Legs are adjusted to smallest setting using the buttonhole elastics and I was using the cross-over snaps on the waist to get a snug fit.
Charlie Banana OS pocket with small insert. You can see the fit looks a little bit better already as he had put on some more weight at this point. It was still fairly bulky on him here though.
Once J hit 3kg we got a really good fit with the Best Bottoms shell and a size small Snappy Nappy insert. I was also able to use it over snappi'd newborn/preemie prefolds. This should fit most newborns from birth.
*** 3.2kg ***
With J over 3kg and almost weighing as much as an average newborn we tried on the first WAHM diaper - this one was an OSFM hybrid fitted made by Ubuntu Baby (previously Hippie Safari Handmade - not affiliated to this blogger). While the diaper was bulky on him, we did get a snug fit around the legs and waist using the fold-down rise, so it would've contained everything.
*** 3.3kg & 54cm ***
Alva OS pocket on the bum here, it is stuffed with a single microfibre insert. While it fit around the waist (using the cross-over waist tabs), we did have leg gaps at this point still and the overall look of the diaper is fairly poufy.
Bottombumpers OS AIO is one of the trimmest OS options we own, so I was curious to see how this fit would translate on a newborn. We still had huge leg gaps at this stage though. Definitely not a viable option for newborns as pee/poop would leak right out.
J is wearing a Bumgenius 4.0 pocket diaper with the small insert in these photos - it actually fit him surprisingly well at this weight (3.3kg), with zero leg gaps and a good fit at the waist at well. It is a little bulky/poufy on, but not excessively so. This could be a viable option from birth if you want to avoid a seperate newborn stash and don't mind a not-so-snug fit.
Still at 3.3kg, this is J in a Bumgenius Elemental (new style). While there are no leg or waist gaps with this diaper, it looks quite poufy on him. Interestingly, we did still have leg gaps at this stage with the old-style Bumgenius Elemental, so there is definitely a difference in fit between the two versions. It is also interesting to note the variance in fit between the Elemental (AIO) and the BG 4.0 (pocket) pictured above.
Another diaper which surprised me with a surprisingly good fit around the legs and waist at this stage was the Cherub Tree Bamboo Velour AIO. In these photos we were only using the sewn-in insert, I removed the snap-in insert for the sake of fit. I must add that this diaper did feel and look quite bulky on him in terms of crotch width though.
Unlike the Cherub Tree Bamboo Velour AIO above, the Cherub Tree pocket diaper still did not fit J at this stage - notice the leg gap in the photos above. I was surprised by this as Cherub Tree is one of the smallest OS pockets and I really liked the fit on my lean toddler. In these photos we were only using the single microfibre insert in the diaper.
Charlie Banana OS pocket fit J a lot better at this weight vs the earlier photos. It looks a lot more in proportion, though obviously still bulkier vs newborn-sized cloth diapers. Changing the insert to a newborn sized one will also make a difference in fit. But in terms of effectiveness, this should contain everything as there are no leg gaps, so that makes it a viable option in my eyes if bulk is not a concern.
Fancypants pocket diaper gave us a good snug fit around the legs and waist. It does look bulky on though, even with just one of the microfibre inserts. But it would be effective in terms of pee and poop containment.
J is wearing a Grovia AIO here, which I thought would've been a decent fit due to being so trim, but I seriously misjudged the size of the leg openings on the smallest rise and waist settings. At this weight we still had huge leg gaps with this diaper, so definitely not a viable option in terms of keeping everything contained.
Here J is pictured wearing a Snappy Nappy OS cover over a snappi'd prefold, however at this stage we still had big leg gaps and the overal fit was quite poofy. Not a good option to contain pee and poop.
*** 3.88kg, 54cm ***
The Cherub Tree AIO finally fit J a bit better at close to 4kg, before this we had leg gaps (I don't have any photos unfortunately). There was still a bit of a leg gap at the top of the thigh and the diaper looked quite poufy on him at this stage still.
My folding skills definitely needed some work here, but overall, I think the Imagine Birdseye Cotton Flat was a pretty decent fit on J as newborn. Being a fairly thin fabric it is nice and trim and it fit well underneath newborn or size 1 covers, while still being absorbent enough to handle his output too. Definitely a great option for newborn phase.
*** 4.2 kg, 2 months old ***
J is pictured here in an Alva pocket diaper and the fit is pretty decent in terms of zero leg gaps and not too much bulk overall. Note that the insert I used here is the newborn Bumgenius insert though, which is smaller than the Alva insert. Using the standard Alva insert would add extra bulk to this diaper.At over 4kg the Bumgenius Elemental (old-style) finally started to fit J and I was quite impressed at the fairly good fit of this diaper - no gaps around the legs or waist and not too much bulk/poufyness elsewhere. For a bigger newborn, this would be a pretty decent alternative to a seperate newborn stash, however you would need to hunt these down pre-loved as they are no longer being manufactured.
I was amazed at how the fit on the Bumgenius Elemental (new version) differed from the old-style pictured above. Even though these photos were taken on the same day, the fit is dramatically different, with this diaper quite poufy on J still, even though it fit with no leg gaps for quite some time at this point.
*** 4.6kg & 56cm ***
Best Bottoms shell pictured here on J, again with a Snappy Nappy size small insert inside - fit is still great. This is the one OS diaper that I really think fit him very well throughout the newborn stage. As you can see, he has grown quite a bit from the first photo in this blogpost - no need to use the cross-over waist snaps anymore.
*** 5kg & 56cm ***
Charlie Banana pocket diaper is pictured here on J at 5kg. We still needed to use the cross-over waist snaps at this point and he was on the smallest leg elastic settings with a single microfibre insert (the small one). While it fit snugly, it did still look bulky on him at this point.
At 5kg the Grovia OS AIO finally fit J with no leg gaps. Quite a trim fit for a OSFM diaper and the narrow crotch definitely helped with that.
J is wearing a Mother Nature AIO in these photos. I was unable to get the waist smaller than it is shown here (even though it does have a cross-over snap) to try to eliminate the leg gap. I do think the bulkiness of the insert contributed to the gap though - without the insert we achieved a gap-free fit around the legs at this stage.
Time for a WAHM fitted again - Ubuntu Baby (formerly Hippie Safari Handmade) fit J quite nicely at this stage using the fold-down rise. Yes it is bulkier than a newborn fitted would be, but in terms of effectiveness it fits the bill.
*** 5.2kg & 58cm (3 months old) ***
At 5.2kg the Bottombumpers OS AIO finally fit J with no leg gaps. A nice snug fit at this stage, helped along by a narrow crotch and trim inserts.
Grovia OS AIO fit J very well at this stage and as you can see from these photos he had one snap open at the waist already at this point.
I only bought the Itti Bitti Tutto OS diaper when J already weighed 5.2kg, so don't have photos of the fit earlier on, but had to include it here to show the perfect fit at this point. I'm pretty sure it would've fit earlier too as it's not even on the smallest waist setting. Lovely, snug trim fitting diaper on a smaller baby.
If you're considering using cloth on a newborn and still undecided on whether to invest in a newborn stash, I hope these visuals helped you. If you don't mind some extra bulk, there are some viable options among the OSFM diapers that will at least fit with no leg gaps - my top picks would be Best Bottoms and Bumgenius 4.0 Pocket.
But for a well-fitting and leak-proof diaper during the newborn phase (2 - 3 months), I still prefer and highly recommend sized prefolds/flats/fitteds and covers.