Should I I be worried? 6 wk twin ultrasound

Alena

I found out at my 6 wk scan I’m having twins. I’m over the moon (and still in complete shock). However, the doctor mentioned the possibility of something called vanishing twin, and based on my scan (if it were to happen) that it’d possibly be the baby with the less visible/bright yolk sac.

We did see yolk sacs in both gest sacs (too early for heartbeats), she just pointed out that one yolk sac was really bright and the other one wasn’t. Has anyone else had a similar experience and gone on to have healthy twins? Should I be concerned that one sac was less visible/bright? Vanishing twin only occurs in like 20-30% of twin pregnancies right?