Nov 20 (Reuters) - Shares of Sotera Health Co, a medical sterilization firm backed by Warburg Pincus and GTCR, surged 17% in their debut on Friday, after the company raised about $1.1 billion in its initial public offering.

The firm's shares opened at $27, valuing it at about $7.5 billion. Sotera had priced its IPO at $23 per share.

Reuters in October had reported that private equity majors Warburg Pincus and GTCR were readying an IPO of Sotera, which could value the firm at more than $5 billion.

Maravai LifeSciences, which is also backed by GTCR, also made its debut on the Nasdaq on Friday and its shares jumped more than 18%.

For the nine months ended Sept. 30, Sotera recorded revenue of $601.3 million compared with $584.8 million a year earlier. However, net income attributable to the company fell about 28% to $5.1 million.

J.P. Morgan, Credit Suisse, Goldman Sachs, Jefferies, Barclays, Citigroup and RBC Capital Markets were the lead underwriters for the offering. (Reporting by Ambar Warrick in Bengaluru; Editing by Amy Caren Daniel)