Some babies are born without anus due to incomplete formation of the rectum to pierce the anal skin. The rudimentary rectum fail to differentiate completely from the urogenital structures leading to attachment of the rectum to the urinary bladder or anywhere along the urethra.
Thus when these babies are born, doctors will note that they have no anus but have poop coming out of their penis! They will need corrective surgery for this malformation as soon as possible. Most of the times, they may also have associated anomalies with regard to either his spine, heart, digestive tract/esophagus,kidneys even limbs.
^ Some people have all the luck.