Why is Buddhahood attained only by males? Is there a particular reason(s) for a Buddha to be only of male gender?

I'm interested in any explanation in scriptures as well as your interpretations and opinions.
The question is a bit unclear, so here's an answer to what I think your question is.

I believe anyone -- regardless of gender -- can reap the same fruits of the path.  It's all about diligence in practice; gender has nothing to do with it.

Now I recall some misogynistic passages and early injunctions against nuns, but I ignore all that.  I don't think Buddhist scriptures or personalities (including The Buddha) are unerring.  I think that despite having some profound things to say, Buddhism still was a product of its time and place and often failed to transcend those prejudices. 

Fortunately, since Buddhist practice pays off in short order, there's no need for faith, so I don't have to rely on The Buddha being this or that, or claims that a transmission was preserved or any other claim that strains credibility.  I simply see what works and use it.

With that said, Buddhism has some strong females.  The one that comes to mind is Quan Yin (Guanyin), the archetype of compassion.  My local Buddhist Temple gave more prominence to her than to the Buddha, even to the point of stressing her ideal (Bodhisattva) as the goal of practice. Furthermore, in all the Buddhist temples I attended, the Quan Yin statues were much more prominent than the Buddha ones; in fact, there's a nearby Buddhist Temple with a 50 foot tall statue that dominates the grounds.  Who's on that statue? Quan Yin.