Age at first intercourse is inversely related to female cortisol stress reactivity

The relationship between age at first sexual intercourse and salivary cortisol stress reactivity (to the Trier Social Stress Test; TSST; consisting of public speaking and mental arithmetic) was examined in healthy subjects (43 females and 36 males; ages 19-38). Women reporting earlier first intercourse had less intense cortisol increases in response to the stressor (a non-significant trend was observed for males), and faster recovery from the stressor. Results were not confounded by age, oral contraceptive use, depression scores, smoking status, or body mass index. It is concluded that earlier first intercourse is associated with less reactivity to and faster recovery from stress as indexed by this endocrine measure. Results are discussed in terms of genetic and psychological influences on first intercourse and implications for coping with interpersonal stress.