Okay, I'll try again. I replied to this the other day (in some detail) but alas it was lost in the ether!
Kerrie, I think it's fab that you're writing a non-fiction book from personal experience. I'm sure the authenticity would really help you catch a publisher's eye. My advice is to finish the journal so you have a resolution (ie, it's not all about the challenges, but also about how you overcame them so there's an upbeat ending - they like that and I'm sure so do you!)
Then I'd check out bookstores to find books that are in a similar area of interest: non fiction about childbirth/parenting, and see who the publisher is. Then go to the acknowledgements page and see if the author has thanked their agent. That's another person who might want to see your work. So you prepare the manuscript the same way as you would for submission of a fictional novel (info on my "working with louise" webpage on my website: www.louisecusack.com ) and if the publishes will accept unsolicited manuscripts, post it away with a covering letter saying who you are and any writing qualifications/credentials you have.
HOpe that's helpful. Let me know if you need further info (but I have to say, non fiction isn't an area I've had any experience with in publication myself)
Louise