adenomyosis and IVF success / miscarriage rates

Dear Dr. Sher,
I am 39 years old and I was hoping to do a frozen embryo transfer. I have two genetically healthy and high quality frozen embryos. I was set to start the transfer process in mid-July and wanted to consult a different doctor, who suspected adenomyosis and recommended a shot a week before my period starts. I wanted to get a second opinion about what to do in this case and also ask about the risks/percentages of miscarriage as well as implantation success rates with patients with adenomyosis. My periods have always been regular and with no pain and up until this last ultrasound, my previous doctors had not suspected anything. I did have a uterine polyp removed in mid-September. I wonder if this is something that can develop quickly or if it was missed by others.
Thanks so much in advance for your concern.
Melis Taner