The Frog Pregnancy Test in ‘Lessons in Chemistry’ Is A 100% Real Thing

Lessons in Chemistry Episode 3 “Living Dead Things” on Apple TV+ upends everything for Elizabeth Zott (Brie Larson). The love of her life, Calvin Evans (Lewis Pullman), is dead. Their ground-breaking research has been stolen by the same sexist dimwits who had held Elizabeth back before Calvin entered her life. Her dog, Six-Thirty (voiced by B.J. Novak), is unable to communicate his love, guilt, and support outside of his unique voice over to the audience. Oh, and most importantly of all, Elizabeth learns that she is pregnant with Calvin’s baby, instantly putting her professional and personal life in tumult.

But how exactly does Elizabeth discover that she is pregnant in the 1950s? She can’t exactly roll up to Woolworths and purchase a Clear Blue Easy as they didn’t even exist yet! Instead, she purloins two frogs from Hastings and conducts an experiment with them. She someone urinates into the narrow opening of a glass graduated cylinder and then uses a syringe to inject her own urine into one of the frogs. Hours later, when the frog has produced a ton of eggs, Elizabeth knows she is pregnant.

Elizabeth’s frog pregnancy test is not a thing in Bonnie Garmus’s novel, Lessons in Chemistry, but it did exist in real life! The go-to pregnancy test of the 1940s to 1960s was called the Hogben test. Doctors or pharmacists would inject a female frog with the patient’s urine and wait twelve hours. If the frog produced a small sac of eggs, the patient was pregnant. This neat experiment could also work with male frogs, although they would produce sperm, not eggs.

Lessons in Chemistry showrunner Lee Eisenberg told Decider that the idea to include this sequence came from science consultant, writer and supervising producer Teagan Wall.

“I was the same as same as you. I didn’t know that [the Hogben test] existed. It blew me away and I was like, ‘Oh, that has to be in the show,'” Eisenberg said. “It was just one of those moments that was so specific.”

“I was so enraptured by the idea of seeing her clinically do it and waiting. All of it was really, it was tremendously exciting and I thought it was really beautifully told visually, too, by our directors.”

The Hogben test fell out of favor in the 1960s when more modern pregnancy tests began to become developed. Nowadays, Western culture has largely forgotten that a frog-based pregnancy test existed — except for Riverdale. The final season of the CW’s Riverdale, which displaced the main cast back to the 1950s, featured a frog pregnancy test, because Riverdale never passed up an opportunity to be weird.

If you or someone you love would like to try the Hogben test to find out whether or not you are pregnant, the test still works. Because of science. The science still works. Science rules!