That is the BEST argument so far. It uses a solid, non-flexible definition, has a source to back it up, and it agrees with my opinion (the thing I found best of it :kikkoman:).
Also, remember how magnents work: opposites attract. + and + cannot go together, nor can - and -. It dosen't matter which gender is + or -, but that they are opposites.
Plus the only way to be fruitful in this case is to ask the Doctor to take you to a planet in which they have a machine that takes a tissue sample from you, and you become both biological mother AND father. It works on both humans, AND timelords! Perfectly safe, too!