Story highlights A growing number of women and men label themselves as bisexual compared with previous years

It is more common for women to say they are bisexual than lesbian

(CNN) A growing number of women and men say they are bisexual, according to the latest national survey by the Centers for Disease Control and Prevention.

As awareness about bisexuality has grown over the years, it could be getting easier for people to label themselves as bisexual, said Debby Herbenick, associate professor at Indiana University and author of the book "Sex Made Easy," who was not involved in the study.

Researchers asked more than 9,000 people in the United States age 18 to 44 about the types of sexual experiences they have had, whether they are attracted to the same or opposite sex and whether they identify as being straight, gay/lesbian or bisexual. Interviews were conducted between 2011 and 2013 as part of the CDC's National Survey of Family Growth.

Many of the findings about sexual behavior, attraction and orientation were similar between the current survey and the previous (2006-2010) family growth survey. Similar to previous surveys the group conducted, 1.3% of women and 1.9% of men said they were homosexual.

However a few trends stood out. More women reported having had sexual contact with other women: 17.4% in the current survey compared with 14.2% in the 2006-2010 survey. And higher numbers of both women and men identified as bisexual, 5.5% of women and 2% of men, compared with 3.9% and 1.2% respectively in the last survey.

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