This is probably my favorite story of the games so far, which is quite saying something for an mPreg, a genre that, in my experience, tends to be, ah, spotty in terms of quality. You handle it beautifully, from the desperate litany of spells Harry chants--and I knew as soon as I read that list what was going to happen--to Snape's annoyance with the discomforts and inconveniences of pregnancy, to Harry's dogged determination to take care of Snape and make a place for himself in his child's life.
They were both beautifully in character throughout, Snape snarky and snarly and sarcastic to cover his deep-seated insecurity and loneliness, and Harry just trying his best to do the right thing and basically suppressing his own wishes and needs in order to meet Snape's.
And I gotta say, that soupcon of angst near the end was deftly done; it blind-sided--and upset--me damn near as much as it did Harry, and it made perfect sense in context, but oh, I'm glad it didn't last. I *really, really* wanted a happy ending. So thanks for that! And the sex is hot, too. :)
Oh, and I adore your Hermione and, especially, your Pompfrey.