Hi Darily,
I went through two different clinics in Perth and for our first 5 IVF attempts we always had 2 embryos put back in and it was never an issue, with our doctor and the nurses happy for that to happen. On our last 3 frozen embryo transfers we only had 1 embryo put back in (through our own choice), with the last one resulting in the birth of our DD.
It might just be policy with the clinic you are going through but other friends of mine that have done IVF have been able to put back 2. I hope this is of some help and I wish you the best of luck!
Monica