The number of children admitted to US hospitals for sexual abuse doubled between 2010 and 2016, a new study reveals.

In 2016 alone, 8,818 children were admitted to hospitals in the US and confirmed to have been sexually abused - an increase of 71 percent over the rate of abuse hospitalizations from 2010.

The authors of the study, from St Louis University, say the increase may in part be explained by doctors being more watchful for and better informed about the signs of sexual abuse than in past years.

But they also suspect that it's driven by a rise in sex trafficking of young girls in the US.

Between 2010 and 2016, the proportion of emergency room admissions for children that were for sexual abuse more than doubled, as the new study's graph shows

One in five girls and one in 20 boys are estimated to be the victims of childhood sexual abuse, according to the National Center for Victims of Crime.

And the effects of surviving these horrific experiences, which include not only rape and physical abuse, but voyeurism, exposure and child pornography, are carried forward with the victims.

In fact, research suggests that someone who was the victim of a rape or an attempted rape in childhood is nearly 14-times more likely to experience a rape or attempted rape during their first year of college.

That's not to mention the more complex psychological toll that sexual abuse enacts on a child.

People who were victims of childhood sexual abuse are more prone to psychiatric disorders, including depression and schizophrenia as well as physical ailments such as HIV and obesity.

But sexual abuse happens behind closed doors, is often perpetrated by a family member, may be done to a child too young to understand or communicate what's wrong, and the signs may be surprisingly subtle.

Doctors are getting better at spotting those signals, but the problem may be becoming more widespread in the US simultaneously, new research suggests.

Between 2010 and 2016, a staggering 46,993 children were admitted to US emergency rooms, according to the new study published in JAMA Pediatrics.

Of those over 85 percent were girls, and nearly half were between the ages of 12 and 17.

Although the increase in the number of children admitted increased by about 71 percent, that represented a a more than two-fold increase in the proportion of hospital admissions for children under 18 that were for sexual abuse.

The study authors note that there was an increase overall in the number of children admitted to hospital ERs.

Although they didn't investigate the reasons driving this increase, the study authors note that recent increases in human trafficking may well be a driving force in the increase in sexual abuse.

Too often, the two go hand-in-hand.

A study conducted in 2017 tried to work out the risk factors for victims of human trafficking and found that sexual abuse was the most consistent predictor that someone would fall prey to traffickers.

And trafficking is on the rise the whole world over. A United Nations (UN) report published in January found that the number of human trafficking investigations to come through its office has hit a 13-year high.

The US Department of Health and Human Services (HHS), too, highlighted the issue in its own report the same month.

The co-chair of the NEPA Task Force Against Human Trafficking referred to the sexual exploitation of children as 'the nation's fastest growing form of organized crime,' in an interview with the AP.

As US officials have urged greater awareness of sex trafficking, hospitals have attempted to improve physician familiarity with the signs o f sexual abuse.

Physically, doctors can check children for STIs and signs of genital trauma, particularly if they've had an bleeding, bruising or spotted blood on the sheets.

Sexual activity that is inappropriate for child abuse victims' ages is often followed by other age-inappropriate behavior, experts say.

Child victims of sexual abuse may also be anxious and fearful, have regressed to behaviors like thumb-sucking that they'd otherwise be too old for, be more likely to wet the bed or talk excessively about sexual topics.

Their behavior may also have more literal ties to their abuse, such as being resistant to taking their clothes off to bathe or for check-ups or acting fearful around certain people - usually the abusers or those who remind them of the abusers.

'The increased rates of sexual abuse cases observed in this study are coupled with an ongoing concern about the quality of care and the treatment of sexually abused children who are admitted to EDs, which may not consistently adhere to the recommendations for care endorsed by the American Academy of Pediatrics and the Centers for Disease Control and Prevention,' the study authors wrote.