When Robin informs Barney that he is one fourth Canadian he responds by saying, "No! That's not true. That's impossible!" which is the same response verbatim Luke Skywalker has when told by Darth Vader that he is his father in "Star Wars".
There are 128 episodes between the original Slutty Pumpkin episode and this one.
Last episode in which Barney appears without a suit.
When Lily is messing up her words due to her "pregnancy brain", Marshall starts to correct them until she says "funicular", to which Marshall says he has no idea what she means. Funicular means of a railroad operating by cable, or relating to a rope and it's tension.
This episode features two songs parodied by 'Weird Al' Yankovic, who appeared in the previous episode Noretta (2011). Barenaked Ladies' 'One Week' became Yankovic's 'Jerry Springer' and James Brown's 'Living in America' is parodied as 'Living with a Hernia'.