Re: Seeming to self wean at 10 months?
what makes you think he is getting very little milk? Is it a decrease in the number of nursing sessions per day or the length of nursing sessions? A change in the number of wet diapers or drop in weight? If he is eating a good diet of solids you might be able to keep him going with only a few nursing sessions (I'm thinking 3-4?) per day until your milk comes in for the next baby.
If I understand correctly you don't want him to wean, right? If so, I think I'd just encourage him to nurse as much as possible. Offer when he is sleepy or cuddly. My two always wanted to nurse in the bath or shower. Try skin to skin contact and (if you can with the pregnant belly) babywearing. Even with doing all that there is a chance you will not be able to increase your supply to where it needs to be due to your pregnancy. But at least you'd know that you did what you could to encourage him to continue.
At 10 months he should still be getting much of his nutrition from milk- whether BM or formula, so if he does stop nursing altogether you would need to supplement him with something I think. Probably soy formula if he has dairy problems.
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