I think every woman on the planet that is pregnant or has been pregnant identified with Zara's demeanor at Harry's wedding. At that stage of pregnancy, every hour seems like a day and every day seems like a month and there's really no position to be in and be comfortable.
Its all worth it though and now Zara is back doing what she loves to do best. I'm sure those nine months and the troubles and travails of pregnancy are part of her ancient history folder. That's the blessing of being a mother. As soon as the child is born, everything that came before is forgotten as a mother gazes down at her newborn child.