They're not as popular as avocado toast, yet prenups are trending among the millennial generation.

Just more than half of the attorneys in a recent survey cited a boost in the number of millennials requesting prenuptial agreements, according to the American Academy of Matrimonial Lawyers. Only 2 percent saw a decrease among 18-to-34-year-olds.

Across the board, 62 percent of the lawyers polled have seen an increase in the total number of clients who are seeking prenups during the past three years, the AAML said. That follows a fivefold increase in prenuptial agreements over the past 20 years, according to Arlene Dubin, chair of the matrimonial and family law practice of Moses & Singer in New York.

Millennials, in particular, are entering into marriages later, which may mean they have more to protect in the event of a divorce.

In part because of their financial obligations, nearly one-third of millennials said they were putting off getting married and 38 percent said they postponed having children, according to a TD Ameritrade survey of 1,000 adults age 18 and older.