NEW YORK (Reuters Health) – Young age does not preclude fertility-preservation efforts for girls undergoing gonadotoxic cancer treatment, through cryopreservation of isolated oocytes as well as ovarian cortex, a team in Israel reports in the October 27 online edition of Fertility and Sterility.

Lead author Dr. Ariel Revel and colleagues note that ovarian cortex preservation is now routine for prepubertal girls at many cancer centers, but future use of this tissue may be limited.

“We thus currently propose to all patients undergoing ovarian cryopreservation to perform integrated oocyte aspiration from antral follicles of the tissue, followed by in vitro maturation (IVM) and oocyte cryopreservation as an additional fertility-preserving method,” the authors explain.

For their current study, the team at Hadassah Hebrew University Medical Center in Jerusalem analyzed oocyte detection and in vitro maturation success rates in 19 girls, ages 5 to 20 years, who were about to undergo treatment for cancer.

The surgeons performed laparoscopic unilateral oophorectomy on each patient, using a harmonic scalpel to quickly retrieve the ovary and to prevent thermal damage.

All antral follicles were aspirated, and cumulus-oocyte complexes and naked oocytes were incubated for up to 48 hours in IVM culture media. Mature oocytes and slivers of ovarian cortex were cooled to -140 degrees C and stored in liquid nitrogen.

A total of 179 oocytes were retrieved from 17 patients, including 7 from a 5-year-old girl and 8 from an 8-year-old girl. The overall maturation rate was 34% (45/133 oocytes submitted to IVM).

Dr. Revel’s group cautions that this approach is still experimental, but they recommend it for appropriate patients — those at high risk of ovarian failure and with realistic chance of long-term survival — since pregnancy rates after oocyte cryopreservation “do seem to be on the rise.”

“We believe that the patients’ best interest is served,” they add, “as this appears to give them not only a possibility to restore fertility but also conveys a message of hope for a better future, looking into the long-term possibility of parenthood.”

Reference:
Fertil Steril 2008.