I know many people are against implementing any type of schedule in babies this young, but for those of you open to it, I wanted to post what seems to have worked for us.
Barrett averages 3-4 hour cycles throughout the day which consist of eating (20 minutes), awake (40 minutes to an hour), and sleeping (2 hours).
During the day we try not to let him sleep longer than 2 hours straight at a time and make sure not to bundle him up (onsie and receiving blanket max).
From noon until bed time (10pm), we feed him 2oz bottles of breast milk, more frequently (every 2.5 to 3 hours). So, basically he is eating less at each feeding, but eating more often.
Then at his 10pm feeding, I give him both breasts and he nurses for 40 minutes totall (approximately doubling the amount of food and nursing time). Then he goes down for the night and we go to sleep. I make sure to either swaddle him in a heavier blanket or in his fleece kiddopotamus(sp?) swaddler, so he is nice and comfy (but not over-bundled of course).
For the last 4 nights (since changing to this feeding pattern), Barrett has given us 2 blocks of sleep (with a feeding in the middle) through the night. The 1st block of sleep has ranged from 4.25 hours to 5.5 hours (11pm down and up to eat at 4am) and the 2nd block of sleep has ranged from 3 to 4.5 hours (4:30am back down and up for the day around 8am).
So, DH and I are getting a combined average of over 8 hours of sleep for the last 4 nights.
Barrett is gaining weight and has plenty of wet and poopy diapers, so I know he's getting enough. Anyways, thought I would share what has worked for us as I am more than thrilled to feel human again (without needing to take naps throughout the day).
Re: 3 weeks old, BF and sleeping for 4-5 hour stretches at night
Consider yourself lucky.
We have taken the same approach with both of our boys: breastfeeding on demand, letting them sleep during the day when they are tired, etc. DS1 woke a bunch of times each night at this age and it was a huge struggle to get him back to sleep. DS2 sleeps in 3.5-5 hr stretches and goes back to sleep (in his crib nonetheless) like a dream.
And not brilliantly awesome?
Haha!
That's fine, I'll take the luck! DS1 is 6, so it's been long enough ago that I don't remember how I got him to sleep longer at night. He may have totally done it on his own... I was trying to remember and/or figure out what would help DS2 move his long periods to the night time instead of right in the middle of the day. I seriously HOPE the long periods at night are here to stay!