In 2002 I had to go 5 times before my first tandem then at least once for my first hundred SKY jumps, till eventually the fear response had fully ended.
In 2006 I had to shit before every BASE jump at least once and this continued for a few hundred.
If sufficiently scared causes Involuntary Stress Reaction 50% will void bladder (piss) 25% will void bowels (shit)