Oh, how often comes that question: ‘And… how are the nights?’ Since Zoyla has been born, there has been a spark of interest into our sleeping habits, often accompagnied by worried looks for growing bags under my eyes.
I could simply tell you all ‘it’s going pretty decent, thank you’ and move on. But, wouldn’t it be much better if we would let the numbers do the talking? I thought so!

Me posing with our study organism
So I dove into the data again, turning life with a baby into some new lines of R-code (of course with the obligatory pink dots and lines; the little princess wouldn’t allow otherwise). The used dataset is all thanks to my lovely wife, who has been tracking eating and sleeping patterns of our baby since almost the very beginning (see also the ‘sleep-pattern’ graph at the end of this post). Using that wealth of data, I could extract for each night the time between the last feeding of the evening and the first feeding of the morning. The result is presented below:

Time between the two main night feedings (in hours) during the first 4 months of our baby’s life. The line is the result of a Generalized Additive Model.
So what do the numbers say? Well, clearly our sleep is improving! While our brave little girl could not stand more than 4 hours between her feedings at night during the first few weeks (note that the even more intense newborn week 1 and 2 are missing), she rapidly improved her night habits with a peak around 3 months of age. Then, we could often wait 8 (!) hours or more between feedings. That is truly amazing, even considering that these hours start already at around 18h00.
Then, we rolled in to that dark period of the ‘4 month sleep regression’, with a clear dip in the model at around week 14. The baby-books had warned us for that: at around this age, she would temporarily forget part of the sleeping habits we painstakingly built up. We thus went back from 1 to 2 feedings a night for a while (including the half an hour of holding her straight up for her reflux – luckily we are two to tackle the nights).
But now those dark days seem over again, with the curve soaring upwards. Fingers crossed that slope will keep up that pace as, dear lord, one starts to love a good night’s sleep!

They grow so quickly, don’t they?
Supplementary graph

Sleep pattern of our baby in the night since we started tracking when she was about 2 months of age. Green bands are sleep, white bands are awake time, often filled with eating.