Hi! I know EXACTLY how you feel about CD and pregnancy! I have lost 4 stones with CD, then about a stone away from my ideal weight I discovered I was pregnant. I spoke to GP, midwife and surfed the net for info on how to proceed. All sources said the same: stop using CD while pregnant. I also read somewhere (forget where) that mum being in ketosis can harm baby's brain development. Please correct me if I am wrong in this.
Then I thought of following WW while pregnant, after all, it is all healthy eating and no junk, exactly what all pregnancy literature recommends. I went to WW meetings to ask for advice, and they told me to come back to them after the birth. I felt so let down, I even rung their help number to get some answers. I just couldn't understand why I couldn't follow their diet? I still don't understand.
So this is what happened: I was careful about not eating sweets, junk and similar for a while. Some 3 months before birth I lost the plot. I was big, I was miserable about the fact that I was big and I started to eat. And boy did I eat! I ate like I had kittens (6 of them).
Result: I gained almost all the weight back. I had problems getting around, walking, sleeping etc. If ONLY I didn't eat like it was an Olympic sport towards the end all would be fine. But...
So, the conclusion is this: I see no reason why you can't be on WW and gain weight sensibly and slowly (as you need to gain weight while pregnant).
My baby is 5 mths old now, I have lost 2 1/2 stones so far and have 2 more to go to be where I was prior to getting pregnant.
It sounds awful I know but time has passed very quicky, and I will be back to size 12 by summer which is all I want!
Congrats on your pregnancy, don't eat 10 icecreams in a row (like me) eat healthy stuff and don't worry about it!
Good luck!