Sheldon: She chose to have a home birth. Because she wants to live in the stone age, and a cave wasn't available.

Raj: You know, many people believe home births are better because the mother's in a warm, comfortable environment where she can be nurtured by loved ones.
Sheldon: And turn the bedroom floor into an amniotic slip 'n slide.

Raj: [to Amy] If you were having Sheldon's baby, would you really want him in the room?
Penny: Yeah, if he's in the room when they're making the baby, I'll give you $10.

Amy: (Talking about "It's A Wonderful Life") It's great. It's Christmas time, and Jimmy Stewart's really depressed and he's gonna jump off a bridge and kill himself.
Stuart: Don't need to see it, living it!

Penny: Do you ever imagine what that would be would be like, not being born?
Leonard: *Sheldon's knock* What do you think? *Sheldon's knock* What do you think? *Sheldon's knock* What do you think?

Amy: You make jokes about Sheldon but if it weren't for him, I don't think any of us would be sitting in in this room right now.
Howard: Really? Sheldon not being here is the main reason I'm in this room.

Amy: You wouldn't be dating Penny.
Leonard: You don't know that. I've been going to the Cheesecake Factory for years. I could have picked her up.
*Everybody laughs*
Penny: Oh, you weren't joking?

Penny: Hey, you guys ready to order or do you need a few minutes?
Leonard: *mumbles*
Penny: Few minutes it is.

Leonard: Uhh, umm. I'm Leonard.
Penny: Really? You don't sound so sure.
Leonard: No, I am me.

Sheldon: I've seen things. Lady things.
Amy: Listen to me. That is not the way they usually look!

Sheldon: This is no way to make new humans. People coming out of people. Like some dirty magic show.

Mary Cooper: Sheldon Lee Cooper, you get back in this room right now. And bring a mop!
Sheldon: Did you hear that? A mop! I've got two PHDs yet somehow I'm the janitor of my sister's birth canal.

Leonard: Hey, Sheldon sent us all an email. "Happy Holidays from Texas", and there's pictures. *Looks at his phone* Aww, do not open them. Do not open them!
Penny: Oh come on, childbirth is a natural, beautiful - Urgh, it's like someone sawed a cow in half.
Raj: My father is a gynaecologist, I think I can handle it. *Looks at his phone* And ... now I'm gay.

Penny: Doing laundry?
Sheldon: Of course I'm doing laundry. Saturday night is laundry night and I'm in a laundry room, so I believe your inference is justified.
Penny: Oh, "My inference is justified", Sheldon you are so funny!

Amy: Here's another one. Penny, if it weren't for Sheldon, you never would have met comic book legend Stan Lee.
Penny: Great.