AMAG Pharmaceuticals Inc., a U.S. developer of women's health treatments, is selling its Cord Blood Registry business to GI Partners LLC, a private equity firm, for $530 million in cash.

The Waltham, Mass.-based company will use most of the proceeds to pay off the remaining $475 million of principal on debt due in 2023. The transaction is expected to close in the third quarter and the company will update its 2018 financial guidance after that, AMAG said in a June 15 statement.

AMAG President and CEO William Heiden said the sale is key to the company's strategy to invest in and grow sales of its current therapies, which include anemia treatment Feraheme and Intrarosa for a menopause-related condition. The U.S. Food and Drug Administration has also accepted for review the company's application to market bremelanotide for female sexual dysfunction.

Cord Blood Registry, founded in 1992, stores umbilical cord blood samples from more than 600,000 children and has enabled more than 400 families to use the cells for both established and experimental therapies, according to its website.

San Francisco-based GI Partners said in a separate statement that it intends to combine Cord Blood Registry with California Cryobank Inc., a private donor sperm and egg bank. GI Partners did not disclose what it paid for California Cryobank.

Perella Weinberg Partners LP was AMAG's financial adviser, while Goodwin Procter LLP provided legal advice.