The incidence rate of unresponsive thin endometrium in frozen embryo transfer cycles: A case-series of therapy with granulocyte colony stimulating factor

Background: Treatment-resistant thin endometrium (TTE) during in-vitro fertilization isa relatively uncommon and challenging problem.Objective: The primary aim of the study was to assess the TTE rate during frozenembryo transfer (FET) cycles and the secondary aim was to evaluate the effect ofintrauterine instillation of granulocyte colony stimulating factor (G-CSF) in these cases.Materials and Methods: In this cross-sectional study, all of the women who underwentFET cycles with hormonal endometrial preparation in Royan Institute from June 2015to March 2018 were evaluated and all of the cases with TTE diagnosis (endometrialthickness < 7 mm after using high doses of estradiol) were included. In the eligiblecases, 300 μgr of G-CSF was infused intrauterine. If the endometrium had not reachedat least a 7-mm, a second infusion was prescribed within 48 hr later.Results: During the study, 8,363 of FET cycles were evaluated and a total of 30 infertilepatients (0.35%) with TTE diagnosis were detected. Finally, 20 eligible patients wereincluded. The changes of endometrial thickness after G-CSF therapy were significant(p < 0.001); however, the endometrial thickness did not reach 7 mm in nine patients(45%) and the embryo transfer was canceled.Conclusion: It was found that the rate of TTE during the FET cycle is very low andintrauterine perfusion of G-CSF has a potential effect to increase the endometrialthickness in these patients; however, the rate of cancellation was still high and poorpregnancy outcomes were observed.

Keywords:

Granulocyte colony-stimulating factor , Cryopreservation , Embryo transfer , Endometrial diseases