I think any mom is at risk for PPD any time in that first year (and it really can develop later after the birth, not just in the first few weeks!). A traumatic experience could certainly add to those risk factors. I think it's wonderful that you're being proactive and thinking ahead.
Get your support network in place for afterward and have your husband on high alert, your pediatrician (so when you're there for appointments he/she can also ask how YOU are doing), and maybe enlist a friend who has been there (or who is just perceptive) to follow up with you throughout that first year to see how you're doing.
You may get it, you may not. Hopefully not! And if you DO, know that there wasn't anything you did or didn't do to cause it. It's an equal-opportunity thing, just like pre-e :/
I suspect I had PPD with my firstborn but it was never diagnosed. And I definitely had a big downward swing when my second child was around 8m and started eating solids. Hopefully this next kid will be a different story.
DS born Dec. 2008 at 38.5w gestation. Mild PE diagnosed 3 hours before he was born
DD born Dec. 2010 at 40w1d. BP was slightly elevated since 37w, and climbed while in labor (started on my own). Severe PE diagnosed hours after DD born.
DD born Sept. 2013 at 38w. Induced (and I had to fight for it!) due to high blood pressure. No protein, but had brisk reflexes and clonus after delivery. Doc gave me a mild preeclampsia diagnosis anyway and said I'm likely to be a chronic hypertensive later in life.