Jenna Marie West was born to Joe West and Cecile Horton on May 22, 2018 at S.T.A.R. Labs in Central City. Later at the West house, Jenna was introduced to Team Flash, received as their "newest member". She also met her future niece, Nora West-Allen. Jenna started to cry as the team discussed time travel. Her mother read her mind and learned that she was hungry, causing Cecile to realize that she still had her powers, which she believed was only linked to her pregnancy. 
Along with her family, Jenna attended the charity softball game between the Central City Police Department and Fire Department. Suddenly, a hypnotized firefighter nearly dropped a bomb in the stadium, but a hypnotized Nora threw it into the air, saving Jenna and the other attendees.
Several months later in the fall, Jenna was taken out for the day by her father.
During the Anti-Monitor Crisis, Jenna as well as everyone in the multiverse except for the seven Paragons, was killed in an antimatter wave by the Anti-Monitor on December 10, 2019, only to be restored a month later, after the Paragons and the Spectre created a new universe.
In spring 2020, Jenna and her parents went into Witness Protection in order to keep her safe from the danger that Black Hole presented, especially after the organization hired Rag Doll to kidnap Cecile; Jenna stayed with her older sister Joanie.
- While Jenna inadvertently activated her mother's latent meta-human gene while still in the womb, it is unknown whether she herself will be a meta-human or not in the future.
- As a baby shower gift, Wally West brought Jenna a bassinet that once belonged to Moses.
Behind the scenes
- In the comics, Jenni Ognats is the granddaughter of Barry and Iris West-Allen. She is a speedster called XS in the future, a member of the Legion of Super-Heroes and one of the few African-American members of the West bloodline. On the show, Jenna is also African-American, just like the rest of the West family.
- Also, in the show, the name XS is given to Nora, Barry and Iris's daughter and Jenna's niece from the future.