There are a few other trends at work. One is that people are getting married later in life (and women are having fewer children and later in their lives). In 2018, the median age for a first marriage was 27.8 for women and 29.8 for men, about four years older than the median ages in 1986, which were 23.1 for women and 25.7 for men, according to U.S. Census Bureau data.