i wont try the stairs. sounds painful. there is a famous tennis player, Becker, who tried and got the woman pregnant.

https://www.telegraph.co.uk/news/cel...on-stairs.html

"small talk and then in the next possible corner we got down to business."
In his autobiography, Stay a Moment Longer, Becker stated that the fling "was the most expensive five seconds of my life".
He is now paying substantial maintenance for that lovechild, and his subsequent divorce cost him more than £20 million.