Two sacs???

Question

Hi there!
I did IVF and transferred one embryo on 3/14
I went for an ultrasound 5w5d and they saw a gestational sac and yolk sac
Returned for an ultrasound at 7w2d. They saw a perfect baby and heartbeat of 140.
They also saw another sac that appeared empty and a little smaller.
Should I have this rechecked? Could it possibly be twins?
Anyone have anything similar??

Answer

Did they say it was a gestational sac? it could be a SCH which is more common with IVF pregnancies. 
It will look like a sac on the ultrasound but it isn’t. 
If they said it was another gestational sac, I’m sure they’ll rescan in a couple weeks to check!