How does the Catholic church explain Matthew 19:9, which seems to allow divorce in case of sexual misconduct?

[Matthew 19:9 (NIV)](https://www.biblegateway.com/passage/?search=Matthew+19%3A9&version=NIV) > I tell you that anyone who divorces his wife, except for sexual > immorality, and marries another woman commits adultery. On a simple examination, it seems to imply that sexual immorality, for example, adultery, constitutes grounds for divorce. Yet this is not the Catholic interpretation. What is the Catholic explanation of this verse?