The disappearance of fetal folloMng birth

The [etal lung at term contains a large amount o[ extravascular water which [ully expands the [uture air spaces. This study on [uU-term newborn rabbits shows that the extravascuIar fluid disappears slowly over a period o[ several days, initially more rapidly in those delivered vaginally as compared with those delivered by cesarean section. The mechanisms o[ removal o[ the fluid are discussed. To our surprise, lung blood volume did nat increase as was anticipated.