Webb wouldn't permit it, I guess.
Her conception & birth was needed to get Bill Clinton back into the Arkansas governorship. Voters love to vote for new parents, so they had to have a baby, whether or not they wanted one. Either way it was a necessary career move for Bill & Hillary.
The rest of us were most likely conceived more randomly and the majority of us are probably accepted conceptions more than wanted and or planned conceptions. Life goes on, if it is allowed to do so.