Pulling out is NOT reliable birth control
There are live sperm swimming around in your pre cum n
and doing it 'standing up' dosent prevent pregnancy either lol
The
"Withdrawal Method" (aka Pulling Out) has an efficacy rate between 78-96% - depending on the skill of the man to know when to pull out as well as other factors.
Also, Pre-Ejaculatory fluid (aka Precum) in and of itself does
not contain sperm. However, there are factors and situations in which a man's precum will contain sperm.
That being said, while it's unlikely a woman can get pregnant from
just precum itself, it doesn't mean that pregnancy can't happen. This is true with
all forms of birth control, except complete abstinence.