Shelbyville Fertility Clinic is a fertility clinic in Shelbyville.
Homer visited the clinic to donate sperm under the false name, Thad Supersperm. He donated enough sperm to buy a Corvette.
When Homer found out that his sperm could not make babies any more, Marge and he visited the clinic again to take his sperm back. A young couple wanted to take the last of Homer's sperm, but when they saw Homer, they gave it back without argument.
There is also a billboard with many photos of babies who all look like Homer.