Having the Sex Talk With Children
The American Academy of Pediatrics encourages parents to start communicating about sex and sexuality when their children are very young—starting with teaching toddlers the correct terms for body parts and how boys and girls are different right up through discussions about sexual behavior. In many ways, parents are in an ideal place to do this because they know their child and know the family's values and beliefs about these issues.
Discussions about puberty (what to expect and when to expect it, etc.) should start prior to puberty, usually by age 9 or 10. If parents have established open communication with their children, they are in a position to pick up on their child's readiness to discuss topics such as masturbation, nocturnal emissions, sexual orientation and sexual behavior. This might happen because a child asks a specific question, because of something they view together on TV, because of something parents hear their child say or because of topics covered in school health class. Parents are encouraged to answer their child's questions and concerns as openly and honestly as possible, keeping in mind that the child may be asking one simple question and is not interested in or ready for a whole "talk."
Teens benefit from knowing their parents' values and opinions on topics such as sexual activity and contraception; the teen may still make choices different from his or her parents but, hopefully, there has been an open discussion first. Research has shown that teens are more likely to make responsible and safe choices regarding sexual behavior if they have both the facts and a sense of their own values first.
In short, there is no "right time" to have the talk. In fact, hopefully parents will have many talks with their kids on these topics, based on the child's age, developmental maturity and interests.
In addition to talking about these issues, many parents find it helpful to give kids one or more books that discuss puberty, adolescent emotional issues, periods, sexual feelings etc., so that the child can read about whatever interests him or her at that time. It could be acne one day, peer relationships another day and condom use yet another day. There are a number of excellent books written for parents to help you navigate these tricky areas; check the parenting section of your local bookstore or library.