In vitro maturation rates in young premenarche patients

The in vitro maturation yield in oocytes retrieved from premenarche patients undergoing ovarian tissue cryopreservation is low.

Volume 112, Issue 2, Pages 315–322


Gilad Karavani, M.D., Natali Schachter-Safrai, M.D., Ariel Revel, M.D., Talya Mordechai-Daniel, Ph.D., Dvora Bauman, M.D., Tal Imbar, M.D.



To evaluate in vitro maturation (IVM) efficacy and oocyte retrieval rates after ovarian tissue cryopreservation in young premenarche girls facing chemo- and radiotherapy.


A retrospective cohort study.


University-affiliated tertiary medical center.


A total of 84 chemotherapy-naïve patients ages 0–18 years referred for fertility preservation between 2004 and 2017: 33 premenarche and 51 postmenarche patients.



Main Outcome Measure(s)

IVM in the pre- and postmenarche groups and in the subgroups of very young (up to age 5 years) and older (5–10 years) premenarche girls.


The number of oocytes retrieved did not significantly differ between the postmenarche and premenarche groups (10.8 ± 8.5 and 8.1 ± 6.8, respectively). However, the overall IVM rate was significantly higher in the postmenarche group (28.2% vs. 15.5%, respectively; odds ratio = 0.47). A separate analysis for patients up to 5 years of age demonstrated significantly lower oocyte yield compared with the older (5–10 years) premenarche girls (4.7 ± 5.2 vs.10.3 ± 7.0 oocytes, respectively) and much lower IVM rates (4.9% and 18.2%, respectively). Correlation of age with number of retrieved and matured oocytes showed a positive significant correlation (r = 0.45 and r = 0.64, respectively).


IVM performed after ovarian tissue cryopreservation in premenarche girls and specifically in very young girls (4 years and younger) yields substantially decreased maturation rates compared with postmenarche patients, raising a question as to the utility of current IVM technique in this age group. Further studies are required to assess modification of the IVM technique for young girls.

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