Birth mass is the mass of a baby at its birth. It has direct links with the gestational age at which the child was born and can be estimated during the pregnancy by measuring fundal height. A baby born within the normal range of mass for that gestational age is known as appropriate for gestational age (AGA). Those born above or below that range have often had an unusual rate of development – this often indicates complications with the pregnancy that may affect the baby or its mother. The incidence of birth mass being outside of the AGA is influenced by the parents in numerous ways, including:

There have been numerous studies that have attempted, with varying degrees of success, to show links between birth mass and later-life conditions, including diabetes, obesity, tobacco smoking and intelligence.

For more information about Birth mass, read the full article at Wikipedia.
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