What do you suggest if my unborn child has just been diagnosed with hemivertebrae, i have no idea what to do?

Close observation: A child with hemivertebrae has wedge shaped vertebrae caused by abnormal development of the segments of the spine./ It can lead to scoliosis and compression of nerves. Your child will require close observation for these complications and immediate care should he start to develop them. A nice discussion is here http://embryo.asu.edu/pages/congenital-vertebral-defects