There is a common belief that there is lots of sperm in precum. In the
research that has been done, very little, if any is found in it.

That would mean that if an ejaculation happened hours ago and there was
urination, there is no viable sperm left in the urinary tract and not in
precum. Sperm is actually very fragile, and precum is designed to clean out
the urethra of the male of any organisms that might harm sperm. The acids in
urine do that. So if a male urinates he often is killing any sperm that might
be left anywhere in the tract.

Sperm must be in semen and protected to live at all. As males get sexually
excited they produce, mostly unknown to them, a small amount of precum that
does not contain sperm (though it may have viruses or bacteria in it). Unless
that precum is produced inside of the vagina during sexual arousal it is not
at all likely to create a pregnancy.