Here's what happened on my ride into work this morning. I drive my 16-year-old, because it's right down the street from my work. This morning we hit the doughnut shop, so we had about 15 minutes in the car as opposed to our usual 7. I mentioned a news article about a woman wanting her school district to ban a book her middle school daughter read because it talked about masturbation, suicide, and teen sex. My son pontificated that Middle School kids know most of the terms, and by HS they know the details of sex. (Oy.)

He then said that there's a pregnant girl in one of his classes, and the expectation at school is that there'll be one pregnancy after the Homecoming dance, one after the Junior Prom, and one after the Senior Prom. As I'm argh'ing at him, he said, "I know, mom, use a condom." I said, "No--keep it in your pants!" I reminded him that a pregnancy messes up your life plans, which he knows because he watched it happen to a talented acquaintance in his jazz band.

Then this conversation:

Son: "But there's a pretty safe time to have sex."

Me: "No, there isn't."

Son: "Yes, there is--someone told me."

Me: "No. People might think that the safest time to have sex is right after a woman finishes her period. But that's wrong. Italian women used to say 'Eat broccoli if you want to have a boy.' We used to think that was an old wives' tale. But what broccoli does is alter a woman's vaginal pH. You know, acid and base."

Son: "Yeah."

Me: "Okay, some women have vaginal fluid that's naturally more acid or more basic. Some women's fluids are naturally more hostile to male sperm than female sperm. So they kill off one kind of sperm and are very receptive to the other kind, letting it get through to the egg. But some women have very receptive fluids and the sperm can wait in there until ovulation, and then, even if they haven't had sex for several days, wham! Fertilization. I'm not making this up."

Son: "I know you're not, mom."

I work in AIDS research, so my sons always get squishy, body-fluid details when they ask about sex/AIDS/STDs/pregnancy.

This conversation happened at 7:15 this morning! I did NOT expect to start my day discussing vaginal pH with my teenager.

But this will maks a good scene in one of my books.