For a while I was hoarding my PTO (paid time off, what we have instead of sick/vacation leave) for use after the baby was born. Then I realized that getting up early and going to work early to make up for the hours I missed for doctors' appointments, in order to not use PTO, was silly. Because sleep right now is worth way more than an extra hour or two of PTO in the bank.
On a similar note, I've realized that I've started to really value the weekend mornings that I wake up early and get up early. Because I know that I wont have time that's purely my own, well, ever again. So, here I sit in the baby's room, enjoying the cool morning breeze, looking out at the beautiful scaffolding on the side of our condo building (I really hope they get done with renovations soon). We have to go to childbirth class at 9:30. But it's only 7, so I have some time before I have to get ready. And I plan to eat my breakfast and drink my coffee and enjoy the quiet. Or semi-quiet, as my getting up triggers what I call "cat crazy time", so they're running around like lunatics. But I can ignore them.