Babies are generally considered newborns from birth up to about 28 days (4 weeks) according to the World Health Organization (WHO). However, the exact length of the newborn phase can vary depending on the source:
- WHO defines the newborn phase as the first 28 days of life.
- Some experts and parents informally extend the newborn phase to 2 or 3 months of age.
- Many medical professionals consider the newborn stage to last up to 12 weeks (about 3 months).
Thus, while the strict clinical definition is up to 28 days, it is common to refer to babies as newborns for up to 2 or 3 months after birth
. In summary, the newborn period is typically between birth and 1 month, but can extend up to 3 months depending on context and expert opinion.
