On December 12, 2019, YG Entertainment officially trademarked the name BABYMONSTERS. On February 18, 2020, the company also trademarked the name BAEMON. Previously, BLACKPINK's Jisoo mentioned in an interview that BABYMONSTERS was among the group's potential names pre-debut.
In February 2020, YG Entertainment unveiled two Chinese female trainees, Jane Wang and Vicky Wei, through the Chinese survival show Idol Producer 3. In the trainees' profile descriptions for the show, the name BABYMONSTER appears; also, they introduced themselves using the group name in the show's first episode. On September 1, 2020 a YG Plus performance expectations report stated that the new girl group "BABYMONSTER" is ready to debut. On November 13, 2020, a financial report from Hana Financial hinted that YG Entertainment's will be debuting a new girl group in early 2021.
On January 2, 2021, media outlet EDAILY reported more than 10 entertainment labels are planning to debut their new boy and girl groups this year, including YG Entertainment's new girl group in 2021. On February 5, YGE expressed again through a financial report plans to debut a new girl group in 2021.
On March 1, 2021, questioned during an interview about the background voices in the song "IYAH", Yoon from WINNER replied that the voices belonged to members of TREASURE and the future members of YG's new girl group.
On May 18, 2021, OSEN exclusively reported that YG will be debuting a new girl group in the 2nd half of 2021. Later that same day, YG Entertainment confirmed the news. In August 2021 several articles stated that YG Entertainment intends to introduce its new girl group in the fourth quarter of 2021. However, no debut in 2021 came to fruition and by November and December of 2021, several articles stated that the group's debut would take place sometime in 2022. A recent leak released by DC Insider revealed that BABYMONSTER would be debuting in the second half of 2022, sometime after August.