10 Most Insane Friends Fan Theories

9. Eating Mockolate Made Monica Infertile

In the show's final season, Monica (Courteney Cox) and Chandler (Matthew Perry) finally end up having twins via a surrogate, due to Monica having an inhospitable uterus and Chandler possessing low-mobility sperm.

And a brutal fan theory has an explanation for the backstory behind Monica's fertility issues, which goes all the way back to the early season two episode "The One with the List."

In the episode, Monica has a job interview where she has to prepare some desserts using the new chocolate substitute "Mockolate."

It's vile, of course, with Phoebe describing it as "what evil must taste like," and in a follow-up interview, Monica learns from the interviewer that Mockolate never ended up getting FDA approval ("Something about laboratory rats"), before the interviewer expresses scarcely-veiled concern at how much Mockolate she may have consumed while cooking.

Given that Rachel and Phoebe (Lisa Kudrow) are both seen spitting out the Mockolate dishes they try out for Monica, while Monica admitted to eating "some," it's entirely possible the synthetic chocolate was toxic enough to wreak havoc on her uterus.

Is it unlikely that it'd specifically ruin her uterus with no additional side effects? Perhaps, but it's not a total impossibility.