Breastfeeding

I am cross posting this on all breast feeding/pumping boards.

I am trying to pump during the day and nurse at night. How often should I be pumping and for how long at a time? My DS is 5 weeks and we have had a horrible time nursing and I'm just fed up with all the crying and difficulties. So I have decided to pump for him during the day and nurse him at night. He refuses to nurse during the day and screams through his feedings if I try, at night he is fine nursing. So starting yesterday he got bottles of breast milk. But I don't know how much I should start him with. I don't want to waste the milk. Also how long is milk good after he has drank from the bottle? How much on average does a baby need a day? I want to make sure I am pumping enough to feed him all breast milk. Thanks so much!

It sounds to me like you may have overactive (or forceful) letdown.  This will cause babies to get very upset.  We naturally have more milk in the morning than the evening, so that explains why nursing is easier in the evening.  I suggest you try block nursing.  Nurse from one side for 2-3 feedings, then switch to the other side.  This will help regulate your supply.  Most women with OAL need to block feed for a few months then can go to the traditional both sides at one feeding.  Here's more info:

http://www.kellymom.com/bf/supply/fast-letdown.html

Good luck!