It's known that kids who have been sexually abused tend to start having sex earlier than kids who have not had that experience, possibly due to emotional distress. A new study out today shows that other forms of maltreatment — such as neglect and physical and emotional abuse — also raise the risk of early initiation of sex.

"All types of maltreatment — physical abuse, emotional abuse, neglect, and sexual abuse — increase the risk for emotional distress at age 12 and sexual intercourse by age 14 and 16," Dr. Maureen M. Black of the University of Maryland, Baltimore, told Reuters Health by email.

"Sexual intercourse among adolescents increases their risk for inconsistent contraception and multiple partners — behaviors that expose them to sexually transmitted infections and pregnancy," she added.

Black's team investigated the link between various types of maltreatment and sexual intercourse in 637 14-year-olds and 493 16-year-olds. A strength of the study, Black said, was that "we followed children who had been maltreated (or not) into adolescence, rather than asking adolescents (or adults) to recall their history of maltreatment and initiation of sexual intercourse."

The children have been followed since age 4 as part of The Longitudinal Studies of Child Abuse and Neglect (LONGSCAN). This group of children has a high rate of maltreatment: 79% of children when surveyed at age 14, and 81% at age 16, had a history of maltreatment prior to age 12. They were either sexually, physically, or psychologically abused or neglected.

At age 14, 21 percent of these kids had engaged in sexual intercourse, and 51 percent had had sex by age 16, according to a report in the journal Pediatrics.

According to Black and colleagues, adolescents who had suffered any kind of maltreatment, not only sexual abuse, were far more likely to have sexual intercourse by age 14 and age 16 than adolescents who had not been maltreated.

For example, at the age of 14, teens with a history of psychological abuse were twice as likely to have had sex as those who had not been abused. Physical abuse and neglect were linked to relatively similar increases in risk.

Maltreated youth also had significantly higher emotional distress than non-maltreated youth, and emotional distress explained the link between maltreatment and sexual intercourse by age 14, Black noted. By age 16, factors other than emotional distress explained the link between maltreatment and sexual intercourse.

"Maltreated children are at risk for early initiation of sexual intercourse and should be a focus of trauma-focused interventions that can improve their psychological and behavioral health," Black concluded.

"Evaluations of young, sexually active adolescents should not be limited to risks of pregnancy and infection, but should include a comprehensive assessment that addresses the possibility of maltreatment," she said.