Inside this medical tank in downtown Seoul, South Korea are hundreds of frozen eggs.
They belong to women who, aware of their ticking biological clock, have chosen to buy reproductive time.
They sit in a CHA medical center, part of South Korea's largest fertility clinic chain which has seen demand for its services double over the past two years.
Women around the globe are increasingly exploring the option.
However, CHA's sharp jump highlights what women face in South Korea where the costs of raising a child are soaring and they must be married to legally use their frozen eggs.
34-year-old public servant, Lim Eun-young, is one of 12-hundred unmarried women who froze their eggs with the clinic chain last year.
Lim says she's not ready to start a family due to the cost and hasn't been with her boyfriend for long.
"We're exposed to a lot of information in this era. We hear from married couples and watch reality TV shows about how expensive it is to raise kids in terms of education costs and everything, and all these worries translate to fewer marriages and babies."
With housing and school costs sky high, more and more South Korean women are putting off having children, or not having them at all.
The country has one of the world's lowest fertility rates.
That's despite authorities spending enormous amounts on subsidies and perks for families.
Social mores also dictate the need to be married before having children.
Just 2% of births in South Korea occur out of wedlock compared to an average of 41% for OECD countries.
And under the law, while single South Korean women, like Lim, can freeze their eggs, they can't legally proceed with a sperm donation and the implanting of an embryo unless married.
Jung Jae-hoon is a social welfare studies professor at Seoul Women's University.
He argues that needs to change, noting that marriages dropped to a record low of just over 192,000 last year.
"It can be seen that women's rights are not recognized in a way, partially not recognized, as a person giving birth. So, regardless of whether she is married or not, the government should at least not interfere with her attempts to give birth."
When asked by Reuters if there were plans to change the caveat, the Ministry of Gender Equality and Family said South Korea needs to: "create a balanced workplace and family culture in order to increase fertility rate".
Meanwhile the country is grappling with a demographic time bomb.
A 2020 survey, by the country's gender and family ministry, found that more than 50% of South Koreans in their 20s don't plan to have children when they get married.