Autologous transplantation of cryopreserved ovarian tissue to induce puberty-the endocrinologists' view.

Transplantation of cryopreserved ovarian tissue has been shown to successfully induce pregnancies. Furthermore, puberty may be induced by transplanted ovarian tissue in girls suffering from premature primary ovarian insufficiency (PPOI) due to gonadotoxic therapy. Therefore, the question arises if ovarian tissue cryopreservation should be recommended for puberty induction in prepubertal girls with cancer prior to gonadotoxic therapies. Although this strategy seems to be more natural than administering exogenous steroid sex hormones, there are some disadvantages from the endocrinological point of view. During physiologic puberty, serum estradiol levels increase very slowly, followed by irregular and finally regular ovulations with progesterone production during the luteal phase. PPOI presents as hypergonadotrophic hypogonadism. When transplanting ovarian tissue in girls with PPOI, the elevated gonadotrophins will promote a sudden follicular growth of one or several follicles with a sharp increase of serum estrogen levels and regular ovulations. This will result into an accelerated pubertal development with the risk of overt weight gain, cutaneous striae and premature growth stop possibly leading to psychological implications.
CONCLUSION: Transplantation of cryopreserved ovarian tissue should not be recommended as an alternative to medically induced puberty.