Gestational Diabetes

My wife has been diagnosed with gestational diabetes and she seems to be taking it pretty hard. And, rightfully so, I suppose. I am trying to be supportive, but I am an "information" person. Without it, I just feel lost and my support is lessened.
At her sugar tests with the physician, she was highest after fasting (20 points too high) and right after meals (2 points too high). After a consult with a diabetes specialist, we have begun a diet to combat the high levels. Primarily, lower (contolled) carbohydrates.
Oddly enough, her blood sugar levels are acceptable during the day. In the morning (prior to eating), her levels are highest, or after fasting. Today was her first "self test" and registered 99. She ate breakfast and tested and hour later which was high also. But, all subsequent tests during the day were "normal", even after meals. She believes a test three hours after a meal would be high also, due to the long period after eating.
Why would lack of eating cause blood sugar to elevate? How can we keep the levels lower other than diet and exercise...Timing? Realistically, how can this affect my wife and newborn, post delivery? How often does gd affect women and their children long term? Any help would be greatly appreciated. I will also croos-post into the diabetes forum of this site. Thanks!