Season 4: Episode 85: The One With The Embryos
Phoebe goes to the hospital to get fertilized with Frank and Alice's embryo. Because Frank and Alice can only afford to pay for the one session with the doctor, they decide to up their chances by implanting all five embryos. Feeling the pressure to conceive, Phoebe spends the rest of the day with her legs in the air. That night, a pregnancy test confirms that Phoebe is indeed expecting. Meanwhile, the guys challenge the girls to a trivia contest where the subject matter is ... each other. With the game tied, Monica ups the stakes by betting and losing their apartment to the guys.