Not until the 4-6 week window. When you have established breastfeeding as the NORMAL way he gets food and he has committed to in terms of work. Getting milk from a bottle is much easier than getting it from a breast. Because your breast only release milk if actively sucked. Whereas bottles continually drip into their mouths and all they have to do is swallow. Which is why if you introduce it too soon they often reject the breast. Because they KNOW their is an easier way. Whereas if you give it at least 4 weeks, they learn that THIS IS the way they get food and they associate with YOU their main source of comfort. When you DO introduce a bottle I suggest you have SOMEONE ELSE do it and you not be anywhere around. That way the child will learn that when you aren't there, Bottle=Food. But it will still never be an issue when you are together.