By Joshua Franklin and Rebecca Spalding

Oct 1 (Reuters) - Private equity firms Warburg Pincus and GTCR are readying an initial public offering (IPO) of Sotera Health LLC which could value the medical sterilization company at more than $5 billion, according to people familiar with the matter.

Warburg and GTCR have hired JPMorgan Chase & Co to lead the IPO which could come in 2021, the sources said, requesting anonymity as the plans are private.

The sources cautioned that the company's plans are subject to change and market conditions. Sotera and GTCR did not respond to requests for comment. Warburg and JPMorgan declined to comment.

Warburg, whose president is former Treasury Secretary Timothy Geithner, and GTCR bought their stakes in Broadview Heights, Ohio-based Sotera in 2015 and 2011, respectively.

Sotera sterilizes medical equipment and offers quality testing to the pharmaceutical and medical device industries, areas that continue to be in demand despite the wider economic slowdown.

A string of healthcare firms, such as online prescription drug platform GoodRx Holdings and primary care provider Oak Street Health Inc, have sought to go public this year as the coronavirus outbreak has either not affected their business or has provided a boon.

Sotera's IPO comes after its private equity owners sought to sell the company in 2018, Reuters reported at the time. However, the sale plans were abandoned after the company faced lawsuits by residents living near one of its Illinois factories that alleged emissions from the plant caused cancer and other health problems.

By going public now, the firms are seeking to capitalize on investors' enthusiasm for new listings, particularly in the healthcare and technology sectors.

Shares of newly listed companies have often surged in their first day of trading in recent months as investors seek to allocate money to growing businesses amid wider economic uncertainty. (Reporting by Joshua Franklin and Rebecca Spalding in New York; Editing by David Gregorio)