What happened, in summary

A 40-year-old woman found a lump in her left breast. Ultrasound showed a 27 by 16 mm breast lesion and suspicious axillary lymph nodes. Core biopsy confirmed invasive ductal carcinoma. The tumor was negative for estrogen receptor, progesterone receptor, and HER2, consistent with triple-negative breast cancer. Because chemotherapy was considered urgent and could affect fertility, she was referred for fertility preservation before cancer treatment. She and her spouse chose embryo cryopreservation. During ovarian stimulation, an unexpected early pregnancy was discovered. Twelve oocytes were retrieved, and ultimately eight embryos were cryopreserved. The pregnancy was then terminated because chemotherapy needed to begin.

Chemotherapy was started after the fertility procedure, and her breast-cancer treatment was still ongoing at the latest point described. Her long-term fertility outcome using the stored embryos was not yet known.