DOCTOR: Amy, why tell me and not Rory?

AMY: Why do you think? I travelled with you in this TARDIS for so long. All that time. If I was pregnant for some of it, wouldn't it have had an effect?

AMY: I don't want to tell Rory his baby might have three heads or, like, a time head, or something.

DOCTOR: What's a time head?

AMY: I don't know, but what if it had one?

DOCTOR: A timehead.

AMY: Shut up.