A literature survey is presented on normal fetal development during the emb
ryonic, pseudoglandular, canalicular, saccular and alveolar stages in the h
uman fetus. Normal anatomical and physiological aspects of fetal lung devel
opment including the fetal pulmonary circulation are described. Factors whi
ch may influence fetal lung growth and consequently may play a role in the
development of pulmonary hypoplasia are discussed, such as intrauterine and
intrathoracic space, lung fluid, fetal breathing movements, normal balance
of volume and pressure in the lung and interference with the blood supply.