The birthing is creative posing with various poseboxes, and just that. As far as I know, there are no poseboxes with birthing poses either, though I wish I had one...
There are no mods that lets the sims give birth in a different way.
The
baby blankets are by Tenshii (some recolors and other outfits
here, and some cute onesies/dresses
here), a lot of the other in Bloom's
child/teen section (both mesh and recolor sections), and I have a huge bunch of baby clothing at
my site (log in required to see).