Q. what is the most critical period of pregnancy where i should be more aware? to the environment , diet ... and things like that... A. The most critical, is unfortunately, the period with the highest chances of the pregnancy not to be noticed - the first weeks of the pregnancy. During the first eight weeks of pregnancy the various organs of the body develop most substantially, also called organogenesis. This is considered the most sensitive period. However, the fetus may be sensitive to insults during the whole pregnancy, so other periods are not "safe".
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