How to defrost breast milk?

masked_rose86

How do I do it?  Do I need to plan ahead and put it in the refrigerator overnight?  Or can it defrost a little faster?  I know it is good for 24 hours.  Is this 24 hours after being pulled from the freezer or from being thawed?  Like if I pull it out the night before and in the morning it is almost thawed, do I call it good for 24 hours starting that morning?

Is a bottle warmer necessary?  We've just used a hot water bath that we put the bottle of cold (refrigerated) breast milk in when we use that.