There are 2 alternatives to invasive biopsi ; Blastocentesis, consisting in teh analysis of the blastocyst fluid , and examination of the culture media.The sampling of BF is performed , leaving the embryo fully collapsed. Because dynamic collapse and reexpansion of the cavity is a phenomenon , the loss of the BF should not be detrimental to the embryo.But success rate is not so high . Another method is after blastulation , investigation of culture media. Also this method carries lots of disadvantages
