Would really appreciate your help, insights, ideas as I am desperate

Iím 34, had 3 previous failed pregnancies (2 abortions due to genetic disorders at week 16, 1 didnít develop properly at week 8).

After that, Iíve done 3 IVF with PGD cycles, each cycle I had 2-3 X 5 day blast transferred (good endometrial thickness) yet no luck.

Any thoughts / ideas on why this is happening? I understand I should have good chancesÖ are there additional treatments, diagnosis, drugs I should take?

Thanks for the kind help,