So leaving aside your secret information, which obviously I can't judge (I'm also highly skeptical about the accuracy of 'open secrets' in most regiments, given that most of those I encountered were at least partially bollocks):Your post makes no sense. The vast majority of women use contraception effectively and there can't be many who are clueless that they're pregnant at five months. I also know the circumstances under which she got pregnant because it was an open secret in the unit and her pregnancy was detected very early on.
As for the invasion date - I guarantee that it was certainly not known to junior ranks in Christmas of 2002 and it was touch and go as to whether we would even take part until very late in the day.
If she didn't know less than 3 months prior to deploying that she was about to deploy, how could she know that she needed to be using contraception? Are you suggesting that any woman in any Army role which might be deployed (i.e. all of them) should be disallowed from having children? Even if you are, was that actually Army policy at the time?
I think my post makes quite a lot of sense. Not so sure about yours.