A more thorough explanation:

PREMARITAL

premarital, adj. Of, relating to, or occurring before marriage. Compare with postmarital.

• They decided to attend premarital counseling before getting married.
• Some people choose to abstain from premarital sex for personal or religious reasons.

The first example illustrates the use of premarital in the context of counseling that takes place before marriage. The second example shows how premarital can be used to refer to sexual activity that occurs before marriage.

Overall, premarital refers to anything that happens before a person gets married. It can be used to describe a wide range of activities, from counseling to sex to financial planning.