In the human: Stages during pregnancy. Embryonic development is marked in green. Weeks and months are numbered by gestation. Different terms are used to describe<unk> , meaning development before birth. A term with the same meaning is the "antepartum" (from Latin ante "before" and parere "to give birth") Sometimes "antepartum" is however used to denote the period between the 24th/26th week of gestational age until birth, for example in antepartum hemorrhage. The perinatal period (from Greek peri, "about, around" and Latin nasci "to be born") is "around the time of birth". In developed countries and at facilities where expert neonatal care is available, it is considered from 22 completed weeks (usually about 154 days) of gestation (the time when birth weight is normally 500 g) to 7 completed days after birth. In many of the developing countries the starting point of this period is considered 28 completed weeks of gestation (or weight more than 1000 g).
Prenatal development
Human embryonic development
Infant visual development
Infant mental health
Fetal programming
Metabolic age
Environmental toxicants and fetal development
Fetal viability