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Labor and Birth

How many weeks will you be when a baby is fully grown?


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February 09, 2012 4:09PM

Gestational age is calculated from the first day of the last period, so you are considered two weeks pregnant on the day you conceive.

Keeping that in mind, a baby is now considered full term at 39 weeks of gestational age (or one week before the due date, which is set at 40 weeks of gestational age).

Babies used to be considered full term from 37.5 to 42 weeks, but recent research has changed this. Babies do best when they deliver AFTER 39 weeks have passed, as prior to that a significant risk of prematurity (breathing problems, etc.) still exists. Elective deliveries (e.g. repeat cesarian sections) are no longer done prior to 39 weeks unless maturity studies (amniocentesis) are done at most institutions.

Similarly, babies tend to develop more problems after 41.5 weeks (low fluid, possible cord accidents, poor growth), so delivery is recommended once this point of pregnancy is reached.