Transfer 1 or 2?

Manda • Ttc since 2013. Fertility treatments at CNY fertility January 2016. 3 Timed intercourse with letrozole. BFN 1 IUI bfn. IVF 1 transfer BFn 6 frozen. FET#1 2 transfer BFP (2 stuck, 1 split) Triplets BBG
So I recently had a failed IVF Fresh cycle where we transfered one 5 day blasto. We froze 6 5 day blastos. Now we are gearing up for an FET. The doctors have asked if we want to transfer 1 or 2? I know the basic pros and cons but I thought I would get some feedback here. Hubby and I are 31. I have PCOS and controlled by medication high blood pressure. I guess im wondering what others did and what pros and cons there are especially to transferring 2? (leaning towards 2)