Even after everything Martha’s seen, this is hard to accept. She’s a medical doctor, she knows how reproduction works, and it’s not like this. Yet she can’t ignore the proof.
A tissue sample’s all it takes, the Doctor’s hand is forced into a machine and a couple of minutes later, there she is, a young woman, grown from his cells. Even Sontarans take longer than that!
The method of reproducing people is bizarre enough to leave Martha off balance, but what’s even harder to take in is that this woman is essentially the Doctor’s daughter.
She looks nothing like him.