Sep 28, 2013
I know at least one person has been wondering about which end of the egg comes out first. Not exactly breaking news, but the egg initially moves through the chicken's oviduct small end first. When it reaches the uterus, the shell calcifies, rotates 180 degrees, and moves on big end first. When the muscles of the chicken's uterine and vaginal walls finally contract to squeeze the small end, it helps to expel the egg forward.