Final answer:
The failure of the distal allantois to obliterate can result in birth defects involving the urinary tract, such as urachal cysts or a patent urachus, potentially requiring surgical intervention.
Step-by-step explanation:
When the distal part of the allantois does not obliterate, it means that it fails to degenerate and disappear during the normal development process of the embryo. The allantois is a finger-like outpocketing of the yolk sac that serves as a primitive excretory duct of the embryo and is a precursor to the urinary bladder. In normal development, the allantois should recede and form part of the umbilical cord and eventually become part of the bladder. If it does not obliterate, it can lead to birth defects, such as an urachal cyst or a patent urachus, where urine may drain from the umbilicus. This could require surgical treatment to correct the issue and prevent infections or other complications.