Bf 10 week old help

[SprogletsMum]

Hi my ds is 10 weeks and exclusively bf. He was 6lb13 at birth I think he lost about 6.5% and took 3 weeks to regain his birth weight.
He has all the signs of a well fed baby, he has lots of wet and dirty nappies, his soft spot isn't sunken or bulging, when he's fed his hands are nice and relaxed etc eye
But he's putting weight on really slowly. He's 9lb3 today and on the 0.4th centile. He slowly drifted down to there from the 25th centile but he has followed it for the last 3ish weeks.
My girls gained weight really quick so this has thrown me. If it wasn't for his weight I'd think bf was going brilliantly.
The hv sometimes talks about topping him up with formula but then in the next sentence says she doesn't think he needs it so not really much help.
I don't know what to do. I'd prefer not to have to mess about with formula but equally I don't want to be starving my baby. There's no face to face help available in my area now for babies over 8 weeks apart from the hv. The gp prescribed gaviscon at his 6 week check because he's sick loads. But the gaviscon constipates him so I took him back today and have been given ranitidine and told to change him to formula so he can have milk thickener.
His latch is good and there's plenty of swallowing going on.
I just don't know what to do for the best?

I forgot to say he had his tongue tie divided at 1 week and it's definitely not rejoined.

It may be that he has been finding his natural centile. And is ment to be lowest centile but weight was higher at birth due to other factors. If there are no concerns medically, and baby is alert with content periods, plenty of wet nappies, no signs of dehydration then I would follow your instincts and continue nursing.

I agree with PP. Trust your instincts - 3 weeks of putting on weight and maintaining his curve are good signs, even if it's a slow weight gain.

The slow weight gain is more likely due to reflux and not an issue with your BM, but it doesn't last forever and formula won't necessarily make it better. My DD had reflux and it does normally peak around 8-10 weeks then start to get better. She went down to the 10th centile (from 70th) but is 87th now (at 15 months). She was combination fed as I had a very very low supply, but the sicking up was no better or worse with BM or formula. I read a lot on thickening feeds and many doctors don't recommend it anymore. There are lots of things you can do to help their pain with reflux (keeping upright after feeds, sleeping slightly elevated etc)

Reflux really is the worst, I hope it gets better soon. Ranitidine definitely helped for us - nothing stops the sicking up but at least it makes it less painful for them. I know how awful and worrying it is when they don't seem to be gaining. But he sounds very healthy! You're doing a great job!