What Scientists Know About the First Nine Months

But just how does undernourishment reprogram metabolism? Does it perhaps prevent certain genes from turning on, or does it turn on those that should stay silent? Scientists are racing to answer those questions, along with a host of others. If they succeed, many more infants will find safe passage through the critical first months of prenatal development. Indeed, our expanding knowledge about the interplay between genes and the prenatal environment is cause for both concern and hope. Concern because maternal and prenatal health care often ranks last on the political agenda. Hope because by changing our priorities, we might be able to reduce the incidence of both birth defects and serious adult diseases. --With reporting by David Bjerklie and Alice Park/New York and Dan Cray/Los Angeles

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