It depended on which of my kids it was. My 2nd was a total blessing in the sleep department, but the other 2...aye aye aye. I'd say about 6-8 weeks for the worst of it, but tbh I'm still pretty sleep deprived with a 12 month old. I did make it easier on myself by cosleeping. I think it's a danger to potentially fall asleep sitting up holding a baby or with a baby lying on your chest. So I ended up researching safe cosleeping...as in the minimal pillows, blankets, etc. and the baby slept more on the crook of my arm, not on my chest.
Mama to my boys (04,07,11)