my 12 week nuchal translucency test came back normal, then at my 18 week one, there was a cyst on the babie's brain, and renal pelvic dialation. I went for another scan at 23 weeks, the cyst was gone, and the kidneys were normal (no dialation), but now there is a thickening of the nuchal translucency, and calcifications in the diaphram, the doctor said his main concern was the nuchal translucency, and that it could be a marker of down syndrome, but unlikely because my 12 week tests said low risk. Is this true, and can this thickening be normal, or ia it likely that my baby has down syndrome?