The U.S. government's National Institutes of Health said a study of U.S. children aiming to track 100,000 from conception to age 21 will be launched in January. This would be the largest study ever performed and will cost $3.2 billion and last more than two decades. 

The study to be undertaken by The National Children's Study, will examine factors leading to autism, cerebral palsy, learning disabilities, birth defects, attention deficit hyperactivity disorder, diabetes, asthma, heart disease, obesity and other conditions. A variety of factors from diet of the pregnant women and young children to the effects of chemicals used in plastics will be examined by the scientists in this study. 

NIH officials said they hope to conduct the study at a 105 locations throughout the country in an attempt to try to understand the early life influences that affect these diseases and try to learn new ways to treat and prevent them. Genetic and biological samples would be collected from people participating in the study as would samples of air, water, dust and materials used to construct their residences from the homes of the women and babies. 

Dr. Duane Alexander, who heads the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development, told reporters, "We anticipate that in the long term, what we learn from the study will result in a significant savings in the nation's health care costs."

The project had begun selecting the locations in 2004 when budgetary constraints from Congress delayed the project. Officials said more than $200 million has been spent already of the study’s projected cost of $3.2 billion.

The study is now scheduled to begin in January when the University of North Carolina, Chapel Hill, begins recruiting women from Duplin County, N.C., and the Mount Sinai School of Medicine in New York recruiting in Queens County, N.Y. They would start signing up pregnant women whose babies would then be followed to age 21 with the first data available from 2012 or 2013. 

According to Dr. Peter Scheidt of the NIH, who heads the study, some of the early findings will be about factors behind pre-term birth, which has become more common in recent years.

Around 27 institutions that will take part in the study were named by the NIH, nine had been named previously and a few more would be selected in the future said the NIH. The people in the study would cover wide strata from rural, urban and suburban areas, from all income and educational levels and from all racial groups, the NIH said.

The remainder of the pilot sites is planned in of California, Pennsylvania, Utah, South Dakota and Minnesota with nationwide enrollment set for summer 2010.