Slightly Large Fourth Ventricle

I am 32 weeks pregnant and just recently went to a Pernatologist because I have gestational diabetes. When doing the ultrasound the doctor said that my baby's fourth ventricle was a little larger than what it should be but the others measured just fine. He told me that it was nothing to worry about, that sometimes people with larger heads may have larger ventricles. Is this true? He never mentioned anything about water on the brainj so I didn't think anything of it and I don't go back to see him for over 4 more weeks. He just said he will keep an eye on it. I'm just very nervous about it now that I know more about what it could be. If the doctor hasn't ordered any other tests or asked to see me sooner should I be as alarmed as I am? I just hate not knowing for sure.

[Yao Sun, MD, PhD]

If the perinatologist did not order any further ultrasounds or tests, he is probably not really worried about the size of the ventricle.  It is common to have mild enlargement of one of the ventricles that can still be considered as normal.  If you are still worried, you can call your perinatologist and ask to discuss the issue a little more with him.