If you are the parent of a tween or teen, you’ve no doubt had “the talk” with him or her; or maybe you are gearing up for it. But according to a new study, having this conversation once just isn’t enough. Parents may need to have multiple, recurring talks in order to influence their kids' attitudes toward sex and safe sex practices in the future. This is especially true if a child is having sexual identity issues.

Parents often reported more communication than their kids did, suggesting that parents like to think they’re being more communicative than they actually are.

Almost 470 teens, aged 14-18 at the study’s start, and their parents were asked about how often they were communicating with each other about sex. Then, once a year, the teens and their parent or parents were interviewed again, and each party reported on how much they felt they were communicating.

When the kids reached 21 years of age, the researchers, from Brigham Young University, asked them about their current safe sex practices. In general, teens reported low levels of communication about sex with their parents. Parents often reported more communication than their kids did, suggesting that parents like to think they’re being more communicative than they actually are.

“Whether or not parents think they are talking about sexuality often, children are generally reporting low levels of communication,” said study author, Laura Padilla-Walker, in a statement. “So parents need to increase sex communication even if they feel they are doing an adequate job.”

And in terms of safe sex later on, the team found that having “the talk” just once during the teen years wasn’t necessarily linked to safer sex behaviors at age 21 — but recurring communication about sex was.

“Our current culture is highly sexualized, so children are learning about sexuality in a fragmented way from an early age,” said Padilla-Walker. “Research suggests that parents can be an effective means of teaching their children about sexuality in a developmentally appropriate manner, but that does not occur if parents only have a single, uncomfortable, often one-sided talk.”

Talk about sex more with your kids, she urges, make it not just a one-off event, but a more regular, and less awkward, conversation over time. “Parents should talk frequently with their children about many aspects of sexuality in a way that helps the child to feel comfortable and heard, but never shamed.”

Questions about sex are natural and normal, and kids should feel comfortable seeking information from their parents, rather than looking to the Internet, which may be inaccurate or unrealistic, or relying on friends, who may or may not be well-informed. As Padilla-Walker says, “all children are developing sexually and need continuous and high-quality communication with parents about the feelings they are experiencing.”

So rather than bracing yourself for a single talk, try mentioning issues casually as they come up in conversation, movies, the news or with people in your life and spend time listening to what your son or daughter has to say. Having an open and ongoing dialogue may be the best way to keep your kid safer in the years to come.

The study is published in the Journal of Adolescent Health.