Thanks. In how much interval should we try again?

Hi, I am a male 35 and my wife is 33. We could easily conceive two healthy daughters with single intercourse session each time. We wanted to balance our family and wanted a son. Recently, we tried IVF with ICSI and PGD. Out of the 14 embryos that fertilized, 9 of them went to the blastocyst stage (G...