Document Type : Letter to The Editor
Ankara University School of Medicine, Department of Obstetrics and Gynaecology, Ankara, Turkey
Although ovarian tissue cryopreservation is still considered as an experimental technique, several authors from
around the world have reported successful and promising results. Currently, oocyte cryopreservation seems to be the
most feasible technique for fertility preservation when there’s some kind of a time constraint in adolescents and adults.
However, it has been estimated that a young woman would be expected to have a 94% likelihood of having a live birth
with 20 mature frozen oocytes (1). At age 34 years, however, this expectation is decreased to 90% with 20 mature frozen
oocytes. In addition to age-related limitations, an immediate obstacle for obtaining oocytes in cancer patients is the fact
that only one controlled ovarian hyperstimulation (COH) cycle can usually be performed in these women because of
time constraints, yielding a relatively low number of oocytes and/or embryos. For this reason, results from egg donation
programs cannot be extrapolated to cancer patients, nor can the quality of oocytes be guaranteed. Hence, a combined
fertility preservation technique can be of valuable in increasing the chances of successful future pregnancies following
gonadotoxic cancer therapies. Previously, Dolmans et al. (2) suggested that cryopreservation of bilateral ovarian cortex
followed by COH is a feasible and safe approach to preserve fertility before gonadotoxic treatment, and that the number
of cryopreserved embryos was similar to the controls.
We have been offering the option of the combined technique to fertility preservation patients for a couple of years and
have performed it in a series of eight candidate patients. All patients had enough time for COH before oncology treatments. We first performed laparoscopic ovarian resection for ovarian tissue cryopreservation and then started COH on
postoperative day 0 or 1 in each patient (Table 1). The main point in our findings is that ovarian resection is performed
from the side with less antral follicle count of the patients. We suggest that this approach can increase the oocyte yield in
a single available COH cycle.
The data is limited on the effectiveness of combined technique and more long-term follow-up studies are needed in
larger groups with appropriate controls. According to our clinical experience, we believe that combined technique is
a valid approach, which is expanding beyond the experimental stage and has become a clinical technique for fertility preservation. We particularly suggest selecting the ovary with a low antral follicle count for wedge resection to
increase oocyte yield. The information gathered from large international multicenter reports would encourage physicians to agree that the method should complete the experimental phase and be ready for wider clinical use in female