Government researchers released data Thursday stating that American teens are using suffocation and hanging to commit suicide more than any other method. And suicide rates for young girls and women are rising quicker than for young men.

Researchers from the Center of Disease Control and Prevention reported that the reason for the increase is unclear. Thomas Simon, a suicide expert who aided in leading the study for CDC, said that the data does not “allow us to determine why.” Further, he questioned both conventional and social media along with “access to other methods.”

Although the reason behind the rise in this method is unknown, suffocation is more lethal than common attempt methods by females such as drug overdoses. It usually does end up killing the victim.

The deaths by suffocation rose each year from 1994 to 2012 among both males and females from ages 10 to 24, according to Fox News. It rose to 4.5 deaths per 100,000 among young men by 2012, according to the CDC’s Morbidity and Mortality Weekly report. This was up from 3 in 100,000 in 1994. The rate of suicide among young women went from 0.5 per 100,000 in 1994 to 1.7 in 2012. The overall use of suffocation in suicide attempts increased by 6.7 percent and 2.2 percent annually on average in young men and women.

CDC researchers found that suicide rates among young men decreased from 15.7 per 100,000 in 1994 to 11.9 in 2012. However, rates increased for young women to 3.2 per 100,000 in 2012 from 2.7 in 1994. Guns were the most common method of suicide for young men, but suffocation surpassed firearms in 2001 for young women. Suicide by poisoning was the least common for young men and women.

NBC News reported that suicide is the second-leading cause of deaths in young Americans, and in 2012, 5,000 young adults and teens died by suicide. The CDC is worried that they are giving teens a guide to suicide. Often when a report is issued on a specific method of suicide, researchers see a rise in suicide using that method. However, the CDC wants family members, parents, teachers and friends to have a general awareness of the risks.