I dont know!!! Are you on insulin? Do you eat a small amount of carbs at each meal!! Are you eating enough carbs/food to support you and the baby ?
Do you check your ketones at home? Just because they did not show up the day of your appointment does not mean you have not had them if you are losing weight! I had a lot of ketones when I had a check-up with the GP but when I went to the hospital the next day there was none there!
Sorry I am not much help, but I would say you need to eat enough to support baby and you, if your blood sugars rise do not reduce what youre eating to stop them, it may mean insulin or more insulin to help till after baby is born
No I'm not on insulin. I was just diagnosed 3 weeks ago and I am controlling it with diet and exercise for now. At breakfast time I might not have alot of carbs first thing in the morning, I might eat an omelette, or a banana and yoghurt and then an hour or two later I will have some complex carbs like brown bread. If I eat too many carbs first thing in the morning my levels spike but she said today that I HAD to eat cereal or more bread etc at breakfast time. I think I am eating enough carbs to support me and the baby but who knows? I am definitely eating enough protein rich foods, salad and veggies. I think I am eating enough because I don't feel like I am deprived and I get a wide variety of foods and baby is doing well. I know I'm definitely not having the 70g of carbs per meal that the dietitian wants me to have. Instead of having them all in one sitting I space them out throughout the day so they don't affect my levels. Oh I dunno. Its very confusing.
I'm not surprised that I have lost weight since starting this diet because all the crap I used to eat has been cut from my diet (fizzy drinks, chocolate, take away).
I'm not checking my ketones at home. The GP and hospital have been checking them just and I assumed that because there were none in both samples a couple of days apart that it was ok.
Ok so I assume after your breakfast you check your blood sugars and get a nice reading! But then have carbs in a snack which you I assume do not check blood sugars before or after? So in a way youre probably still going high but not at meal times! now may be someone else who is an expert will correct me if I am wrong (((Please do)))

so all looks good when you show your numbers to Endo but your blood sugars could be going high at other times and no one would know on less they decided to do a HbA1c test which they do not tend to do when diet controlled well my clinic do not any way!! Maybe it might be different for you
My diet seems the same as what you were given carbs at each meal but I avoid carbs at snack time.
From my Diabetitic notes:
Carbohydrates provide us with most of our energy, carbohydrate foods do turn in to sugar after you eat them, but it is important that theres foods are eaten in the same quantity and at regular times throughout the day . This will help keep the amount of sugar in your blood steady and energy levels up.
Chose high fibre,wholegrain options as they release the energy (sugar) more slowly. High Fibre, whole grains also contain more vitamins and minerals, can help prevent constipation and keep hunger at bay!
I know the temptation is there to reduce or cut carbs out to keep blood sugars low!!! but this is not good for you or baby, the diet given is to help us function and make sure baby is getting all he or she needs to grow healthy. if you follow the diet and are getting regular exercise and your blood sugars go high, you may need insulin!! (
YOU have not failed it is not your fault ) it is all down to hormones.
I am on insulin and have had insulin dependent GD 3 other times so far followed the diet but sugars rise any way and then needed insulin, all my babies have been healthy and my GD went as soon as I gave birth

I always eat a smaller breakfast
2 slices of wholemeal bread about 50g with low fat butter
Or breakfast cereals,
All bran 40grams with some milk
If I am exercising straight after breakfast I have some low fat cheese or an egg with my toast .Then I have a piece of fruit or a low fat yogurt for my snack. Midmorning
Hope that helps and probably not what you wanted to hear, sorry
As for ketones yep they can show one day and not the next all depends on how much fluids your taking in to flush them out

as far as I am aware once your loseing weight you produce them so they would be there but its good your getting rid of them, I always had problem with them if I had to go in fasting to the hospital

although once I was kept in because I had a lot of them and was put on a drip to flush them out