Cyropreservation Continues to Improve Fertility Options for Patients with Breast Cancer

Today, embryo and oocyte cryopreservation are 2 mainstays of fertility preservation in the realm of breast cancer treatment, according to Lindsay Kroener, MD, an assistant clinical professor in the Department of OB/GYN at UCLA David Geffen School of Medicine.

Kroener recently discussed the topic during the 39th Annual Miami Breast Cancer Conference®. Her presentation, “Answering Your Patient’s Questions About Fertility,” outlined the scope of the fertility preservation in cancer, different treatment options and candidate considerations, and conversations surrounding pregnancy following cancer treatment. In an interview with Oncology Nursing News®, Kroener highlighted how egg and embryo cryopreservation have evolved over the years to represent the most reliable options for patients.

“These treatments are not going to be for everyone. But in terms [of oncofertility], egg and embryo cryopreservation are the best options we have,” she said.

Specialists conduct ovarian stimulation by injecting gonadotropins (FSH/HMG) to stimulate growth in multiple ovarian follicles. These injections are delivered across 8 to 12 days and initiation usually begins on the second or third day of the menstrual cycle. During this time, patients are monitored every other day via an ultrasound and blood work.

When the follicles reach an appropriate size, they receive a trigger shot to induce egg maturation. About 35 to 36 hours later, the eggs are retrieved. This procedure typically occurs in the outpatient setting for about 15 to 20 minutes, and while the patient is under a conscience sedation.

In the case of oocyte cryopreservation, the retrieved eggs are examined microscopically, and the mature ones are cryopreserved. For embryo cryopreservation, oocytes are fertilized with partner sperm on the day they are retrieved and then maintained in a culture for 5 to 7 days. When blastocyst stage occurs (100 cells) the specimen is cryopreserved.

“Those eggs can either be cryopreserved right at that time, or they can be grown out into embryos (if there's sperm to fertilize those eggs),” explained Kroener. “One of the key things [to consider] is [that], as of 2012, cryopreservation is actually considered non-experimental and so it really offers a good option for our non-partnered patients [who no longer need] to say, ‘Hey, I [need to] go find donor sperm to make embryos.’”