16 week appointment with my new ob

I met my new ob today for my 16 week appointment. No problems, nice heartbeat, another blood test of course. But they said I have to go an 'OB class', before my next appointment. I have absolutely no clue what kind of a class this is or why I have to go! And it's just me, not John. So bizarre! And they didn't do an ultrasound today so no gender yet. I'm planning to book a private one today so hopefully it's not still too early!