Women typically first have sex at 17.8 while men generally lose their virginity at 18.1. This is similar to the average rates of first sex 35 years ago according to “Trends in Ages at Key Reproductive Transitions in the United States, 1951–2010,” by Lawrence B. Finer and Jesse M. Philbin. However, the typical time between first sex and first birth has increased from three years for women born in 1940 to almost 10 years for women born in 1982.The study found that on average, the gap between first sex and first contraceptive use has diminished as contraceptive use at first sex has increased. This bodes well for the prevention of unintended pregnancy among teens early in the high-risk period. Although disparities in contraceptive initiation persist, with Hispanic women lagging behind women of other racial and ethnic groups, those differences decreased over time.
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