You should check what the normal range is for NK cells, if I'm not mistaken it is 3-12%. 11.9% is close, and IVIG is blood transfusion. Do you know what type of blood you are? Are you RH negative?
I was asking the same question, and I still want to know, does ivig and ivf have to go together?
Babydreamstc, you seem to be very fertile, ask your doctor what is the best thing for you. There are some side effects with ivig, don't know them firsthand, but you should look it up on the net. just type ivig, and nk cells. I've been dealing with this for years, but never got a straight answer until maybe 2 years ago, and I just had a miscarriage a week ago. No, not with ivig, these doctors don't seem to be fast enough. Anyways, do some research, and ask your doctor questions, lots of them, and you make the decision, but don't wait like I did. (I'm 42).
Good luck with everything and let me know.