The period between conception and birth of a baby, during which the fetus grows and develops inside the mother's uterus.
Gestational age is the time measured from conception to the current date and is measured in weeks.
A pregnancy of normal gestation is approximately 40 weeks with a normal range of 38 to 42 weeks. Infants born before 38 weeks are considered premature. Infants born after 42 weeks are considered postmature. Following birth, assessing an infant's weight, length, head circumference , condition of skin, hair, reflexes, muscle tone, posture, and vital signs can provide a 'relative' or 'developmental' gestational age. The 'developmental' gestational age may not match the calendar gestational age.