Mixing breast milk and formula

[Snail9]

Just need some advice on mixing breast milk and formula in the same bottle?

Dd is 13 weeks and has had horrific reflux since birth. The only thing that has helped is anti reflux formula. I initially attempted Brest feeding but with a poor latch, limited resources, reflux and my own mental health, I switched to expressing but the reflux was so bad after trying multiple meds that didn't work, we switched to the formula and have had a contented baby since. However I have a huge stash of expressed milk in the freezer which would be such a shame to waste. I'm wondering if anyone has mixed breast milk and formula together? Now dd is older I think she may be able to have 1-2 oz of Brest milk mixed into the formula. So I would make a 4oz bottle as normal and then just add 1oz of Brest milk to it. I found a few conflicting articles online and so if anyone has any advice on whether this is ok to do, please let me know,

Personally I would be happy to do that but treat it like formula for going-off risks.

Eg:

Breastmilk is OK at room temperature for about 4h
Formula is OK at room temp for 1-2h max

So if you have mixed bottles then 1-2h max.

Similarly, sterilise etc as if it's pure formula

My understanding is this shouldn't be done for two reasons 1) you want to prioritise the breastmilk so if you mix it with formula and she doesn't drink the bottle the breast milk is wasted and 2) the type of iron in the two milks are different and bond together making them both less available for your baby.

A work around could be feeding breastmilk first then making a smaller amount of formula second or you could hold onto the breastmilk and use it when she starts solids by adding it as the liquid to things like cereal.

You could do it combination feed style, feed the breast milk first then top with the formula.