<unk>  () includes the development of the embryo and of the foetus during a viviparous animal's gestation.<unk>  starts with fertilization, in the germinal stage of embryonic development, and continues in fetal development until birth. In human pregnancy,<unk>  is also called antenatal development. The development of the human embryo follows fertilization, and continues as fetal development. By the end of the tenth week of gestational age the embryo has acquired its basic form and is referred to as a fetus. The next period is that of fetal development where many organs become fully developed. This fetal period is described both topically (by organ) and chronologically (by time) with major occurrences being listed by gestational age. The very early stages of embryonic development are the same in all mammals. Later stages of development across all taxa of animals and the length of gestation vary.
Prenatal development
Human embryonic development
Infant visual development
Infant mental health
Fetal programming
Metabolic age
Environmental toxicants and fetal development
Fetal viability