06/10/2009 15:08 BST | Updated 22/05/2015 06:12 BST

How Do You Tell A 12-Year-Old About STDs?

I started telling my son about 'the birds and the bees' from about the age of 3 when he asked where babies come from. I started off telling him about it in an incredibly simplistic way: "men have sperm inside them and women have eggs. The sperm swims to the egg and one goes up to it and the two of them together make a baby."

That was enough for him for a few years until one night when he was 6 and we were out at our favourite restaurant when he asked pretty much out of the blue, "But how does the sperm get inside the woman's body?" Luckily, I'd already had a glass of wine by that point. I proceeded to tell him even more whilst the people on the table next to ours eavesdropped. "Well... hmmm... you know how sometimes your willy stands up...? Well... er..."

I was happy with the knowledge that I'd explained the biology of sex, but knew that there's a lot more to it than that.

Now that he's 12, he's started sex education classes in school which focus on the biology of it all. I figured that he was old enough to start hearing a bit more, so the other week I decided to 'have a chat'. I started by telling him that he could always talk to me about anything at all. He rolled his eyes and said, "Are you going to talk about something embarrassing now?"

I told him I thought he was old enough to learn a bit more about sex. I said that I'm sure he had some questions about it and that he should feel completely free to ask me anything and I won't be shocked or get mad or anything... "So, do you have any questions?" "Oh god, mum, no...."

I went on to say that he knew about the biology, but that was only part of it. There were good things about sex and bad things. I wanted to make sure that he knew about them so that he could avoid the bad things.

Next came birth control and how it should always be his responsibility to make sure that his girlfriend doesn't get pregnant by always wearing a condom. He asked, "But what if she's on the Pill?" (he knew more than I realised) "Well, there are other reasons why you should always wear a condom. Have you heard of sexually transmitted diseases?" He had. "Well, you do not want to get one of them."

I went onto explain how some STDs could be treated fairly easily, but others had no treatment at all and could stay with you for your whole life and could even kill you. As I was telling him, I wondered if it may freak him out a bit and give him a weird hang up about sex...

So I explained how sex was a really wonderful thing to be shared by two people who really care for one another. I told him that I hoped he didn't have sex too soon and how he should wait until it feels like the most natural thing to do. And that it feels wonderful. Especially when you are with someone you love and who loves you back... And...

I looked at him sitting there staring back at me. "Do you have any questions you want to ask me?"

"Can I go play on the PS3?"