Doctor Who and Regeneration

In Dr. Who mythology, if regeneration can result in a change of gender, why has it taken The Doctor more than 12 regenerations to become female?

(February 4, 2020) I found this question on an answers website and I guess there really is this conversation still going on about the legitimacy of Jodi Whittaker as The Doctor. Please, people, The 13th Doctor is an incarnation of The Doctor, and Jodi Whittaker has already proved herself. But, it's a worthy enough question to ponder for today. Why did the BBC take so long to place a woman in the position of The Doctor?

If The Doctor (Doctor Who) were blown to smithereens by a land-mine, would he die?

(March 17, 2018)

Time Lords famously are hard to kill, and those who die can cheat death by regenerating themselves. But, what happens if a Time Lord, like The Doctor, dies in an extremely dramatic fashion - like being blown to little tiny bits by a bomb - or vaporized in a nuclear explosion - would that Time Lord actually die even if s/he had several remaining regenerations? The evidence is mixed on this question, so let's take a look.

Smith was 13, Capaldi 14, Whittaker 15, how many regenerations does The Doctor have remaining?

(Sun Dec 31 2017 16:00:00 GMT-0800 (Pacific Standard Time))

The first Female Doctor ever has been minted, now that Jodi Whittaker has taken over the role, but the big question is how many regenerations are left. By any rational regeneration counting, we ran out of regenerations -- supposedly Time Lords can only regenerate 12 times -- but the show has continued on. The in-show explanation is that the Matt Smith Doctor was given a new regneration cycle, letting us enjoy Peter Capaldi as The Doctor. But, how many regeneration cycles are remaining for The Doctor?