This is what "internationally renowned" Sherman J. Silber, M.D., writes in his "completely revised and updated" book "How to Get Pregnant," published by Little Brown and Co. last August: "The biggest fear of most pregnant women is that their child will be abnormal, and the most common abnormality they worry about is Down syndrome. ... These children are severely retarded mentally, and they usually die before their thirtieth birthday." He also writes: "We can prevent couples from having to face the horror of giving birth to children with otherwise devastating genetic defects such as Down syndrome, cystic fibrosis, muscular dystrophy, mental retardation, etc., that terrify every woman who ever gets pregnant."