Effect of Intrauterine Recombinant Human Granulocyte Colony-stimulating Factor (rhG-CSF) Infusion on Pregnancy Outcomes in Patients With Repeated Implantation Failure During Freeze-Thaw Embryo Transfer Cycles: A Retrospective Cohort Study

Abstract

Background: Repeated implantation failure (RIF) is one of the difficulties that hinder the further improvement of clinical pregnancy rate by assisted reproductive technology. RIF has become an urgent clinical problem and hot research topic in the field of assisted reproduction, which is also a challenge for clinicians.

Objective: The aim of this study was to evaluate the effects of intrauterine recombinant human granulocyte colony-stimulating factor(rhG-CSF) to improve implantation, clinical pregnancy, early abortion, multiple pregnancy and live birth rate(LBR) rate in women with RIF.

Methods: A retrospective clinical analysis involving 142 women with RIF was conducted in the  reproductive Medicine Center, the First Hospital of Lanzhou University between 1 January 2015 and 30 June 2018. They were divided into two groups: rhG-CSF group and control group, according to whether or not intrauterine rhG-CSF. In rhG-CSF group (n=47) granulocyte colony-stimulating factor (300 micrograms in 1 mL) was infused into the uterus within five minutes by embryo transfer cathete during the proliferative period of menstrual cycle before freeze-thaw embryo transfer(FET), while the control group was not given intrauterine perfusion. The implantation, clinical pregnancy, early abortion and multiple pregnancy were compared between the two groups.

Results:The mean age for whole study group was 35.3±4.2 years old. There were no significant differences between demographic characteristics in two groups(p>0.05). The successful implantation (28.44% vs 12.44%, p=0.012), and clinical pregnancy (48.95% vs 27.35%, p=0.011) rates were significantly higher in the rhG-CSF group than in the control group. Binary logistic regression indicated that rhG-CSF treatment remained significantly associated with successful clinical pregnancy(OR=2.979, 95% CI=1.262-7.003).

Conclusion: Intrauterine infusion of rhG-CSF can increase embryo implantation rate, clinical pregnancy rate in patients with RIF. In addition, the age and rhG-CSF are the independent risk factors affecting pregnancy outcomes.

Introduction

With the maturity of in vitro fertilization (IVF) technology and the increasing success rate, the clinical pregnancy rate of each transplantation cycle has exceeded 50%[1]. The normal ovulatory patients can even reach 69%[2]. Although assisted reproductive technology (ART) has improved pregnancy outcomes for infertile couples, many couples still remain unsuccessful after several IVF attempts causing deep effect on quality of life and a heavy financial burden[3]. Repeated implantation failure (RIF) is defined as the failure to achieve a pregnancy after transferring high-grade embryos through at least three in vitro fertilization (IVF) cycles to the endometrium[4]. These patients are challenges for the infertility specialist, and the defects of endometrial receptivity is the mainly causes of RIF[5].

Granulocyte-colony stimulating factor (G-CSF) is a glycoprotein that mainly acts on neutrophils to promote their proliferation, differentiation and activationglycoprotein[6],which is routinely used to mobilize hematopoietic stem cells and promote the proliferation of bone marrow mesenchymal stem cells to treat related diseases[7]. In recent years, it has been found that the biological function of G-CSF is not limited to the blood system[8]. G-CSF seems play an important role in reproductive medicine, which is being administered mainly in women with thin unresponsive endometrium undergoing IVF[9], repeated IVF failures[10], unexplained recurrent pregnancy losses[11], improve the process of embryo implantation[12]and endometrial receptivity[13]. Many studies have confirmed that the pregnancy outcomes have been improved in patients undergoing IVF-ET[14, 15]. Therefore, G-CSF has attracted the interest and attention of reproductive medicine enthusiasts and was used to change endometrial thickness. Several studies with different results have assessed the effect of G-CSF on endometrial thickness and IVF success [16, 17]. In the studies of N. Gleicher et al.[18]and Dayong Lee et al.[19], the endometrial thickness, implantation and pregnancy rates were significantly higher in IVF patients treated with G-CSF, whereas in the studies of Eftekhar M et al.[20] and Shivani Jain et al.[21], treatment with G-CSF did not affect endometrial thickness and pregnancy outcomes in IVF patients. This difference may be related to the inconsistent with selection criteria of patients. At present, the effect of G-CSF has been evaluated mostly focus on thin endometrium. The study of G-CSF on pregnancy outcomes in patients with RIF is relatively little. It is currently uncertain whether G-CSF is effective in improving results following the patients with RIF. The conclusion remains controversial and needs further to be explored.

We conducted this study on infertile patients with repeated IVF failure, the efficacy of intrauterine rhG-CSF perfusion on pregnancy outcomes was evaluated.

Materials And Methods

Subjects

Embryo transfer was done for all patients who underwent FET cycle. Patients in the rhG-CSF group received intrauterine rhG-CSF perfusion before FET. The procedure involved the administration of 300ug rhG-CSF(Ruibai,Shandong Qilu Pharmaceutical) through slow infusion into the endometrial cavity using an embryo transfer catheter, after urinary suffocation, lithotomy was taken and placed on the examination bed and the cervix was exposed with a peep, and the vulva and vagina were disinfected with iodophor. The control group did not receive any additional treatment before the embryo transfer. Follicle development was monitored by ultrasonography. Follicle size and endometrial thickness were up to the standard and then decided to be transplanted this week. All patients received routine luteal support after transplantation.

Criteria

Implantation rates were determined by the number of gestational sac on the total number of transferred embryos. Clinical pregnancy was defined as the presence of gestational sac with fetal heart beat by ultrasound 4 weeks following the FET. The early abortion rate was assessed by the number of miscarriages before 12 weeks gestation on the total number of clinical pregnant patients. The multiple pregnancy rate was defined as the gestation of the number of patients with multiple pregnancy to the number of patients with clinical pregnancy.

Results

Dependency Of The Obtained Results

Binary logistic regression model was used to determine the dependency of the effect of rhG-CSF treatment on IVF/ICSI outcomes. When adjusted for the participants’age, BMI, hCG day endometrial thickness, duration of infertility, number of embryos transferred, history of miscarriage and ectopic pregnancy, type of infertility, fertilization and FET cycle, we observe that intrauterine rhG-CSF infusion (OR = 2.979, 95%CI = 1.262 ~ 7.003)was positively correlated with clinical pregnancy rate, and the difference was statistically significant. Age(OR = 0.889, 95%CI = 0.808 ~ 0.977) was another one of the main risk factors affecting clinical pregnancy rate, and negatively correlated with pregnancy outcome as shown in Table 3.Visualization of binary regression analysis using GraphPad Prism 8(Figure 2).Then, ROC curve analysis, reaching an AUC of 0.9559, and p = 0.0001, respectively, revealed that frequency of intrauterine perfusion was a predictive factor for the outcome of clinical pregnancy rate (Figure 3).

Discussion

Embryo implantation is a complex and delicate process, which requires high-quality embryos, well-tolerated endometrium and appropriate immune privilege, in order to achieve successful pregnancy. In our study, the implantation and clinical pregnancy in rhG-CSF group were significantly improved compared with control group, and no differences was observed between the two group regarding early abortion and multiple pregnancy rate. The study shows that rhG-CSF is beneficial to the pregnancy outcome of patients with RIF. which provides reliable clinical evidence for the use of rhG-CSF in patients with RIF and are basically consistent with the related research results abroad.

Comparison with previous studies

In recent years, pregnancy outcomes have been reported to improve in these trials in which G-CSF was used in patients with RIF. Fatemeh Davari-tanha and colleagues[23]published a randomized double blind placebo control trial including 80 patients who allocated to three group(G-CSF, saline and placebo group) indicated that intrauterine G-CSF may increase chemical pregnancy and implantation rate in patients with recurrent implantation failure. This was in accordance with our results in implantation rate. And meanwhile, the study of Maryam Eftekhar[24]in women with repeated IVF failure involving 89 patients who allocated to two group(G-CSF and control group) that indicated higher implantation and clinical pregnancy in RIF who had received rhG-CSF compared with the control group. The conclusion is completely consistent with ours. However, in recent study by Ziya Kalem and colleagues[25]used intrauterine G-CSF administration before ART in the RIF group had an effect on clinical pregnancy and live birth rates. Although the results of this study were no statistically significant, the G-CSF group had better implantation and pregnancy rate than the control group. In addition, different routes of G-CSF administration have also been studied in IVF. In a study on IVF cycles with received subcutaneous G-CSF before implantation by Ashraf Aleyasin and colleagues[26], they concluded administration of single-dose systemic subcutaneous G-CSF increases the implantation and pregnancy rates in infertile women with repeated IVF failure. In another study by Soheila Arefi and colleagues[27], demonstrates the possibility that pregnancy outcome is better in women with repeated unexplained IVF who are subcutaneously treated with G-CSF but no significant between two groups. And in a randomized clinical trial study in 2019, A. Eapen and colleagues[11] investigated 150 women with unexplained recurrent pregnancy loss, they reported that no significant increase in clinical pregnancy with the subcutaneous injection rhG-CSF. They have an equal conclusions compared the previous studies in implantation and pregnancy rates.

Different conclusions were reached in these studies. The differences in administration route, participants’ age, endometrial thickness, and sample sizes could have contributed to the observed differences in the results. In the study of Maryam Eftekhar[24], Aleyasin A[26]and our study, the sample size was larger, rhG-CSF was administered systemically through Intrauterine perfusion pathway, the study populations were younger, and had normal proliferating function. The difference is that saline group was set as the control in Maryam Eftekhar’s study, and the effect of mechanical stimulation on endometrium was avoided. Moreover, our Binary logistic regression analysis concluded that intrauterine perfusion rhG-CSF was an independent risk factor for pregnancy outcomes in RIF patients. The route of administration of G-CSF is also controversial. A meta-analyses published by Ling Zhang et al.[28]concluded that both intrauterine G-CSF and systemic administration treatment had good clinical outcomes after embryo transfer in the patients with RIF. Another, a consistent conclusion has been reached by Ying Jiang et al.[27], in which subcutaneous injection was better. Nevertheless, a retrospective study in women undergoing IVF/ICSI treatments by Hulusi Bulent Zeyneloglu[10] showed that dual administration of G-CSF was significantly more effective than the only method. Combined with our study, the positive effect of G-CSF on pregnancy outcomes in patients with RIF women should be affirmed, but the route of administration needs further study. An article on the correlation between G-CSF dose and pregnancy outcome has no consensus yet.. Using a single dose of 300 ug before the implantation was positive for the pregnancy outcome[29], and 150ug as an intrauterine infusion on day of oocyte recovery did not show a benefit in improving pregnancy outcomes[30]. In our findings, we demonstrate that the predictive effect of intrauterine perfusion on clinical pregnancy rate and it provides a statistical basis for clinical treatment. Live birth rate was no significant differences between the two groups. Could be that whether treatment with rhG-CSSF is no longer a necessary condition for for their continued pregnancy, but it can affect the embryo implantation through its different physiological function before the embryo successfully implantation.

The role of GCSF in implantation and pregnancy

Our results fully illustrates that G-CSF might play an important role in the implantation and pregnancy process. As we all know, G-CSF can improve endometrial receptivity via increasing endometrial thickness[31], in order to make the embryo implantation and clinical pregnancy rate go up[32]. At present, there is no unified view of the specific mechanism of rhG-CSF in assisted reproduction. Salmassi et al. proposed that G-CSF level in serum and follicular fluid was a predictor of IVF outcome[33]and its participation in the mechanism of ovulation as described above is quite clear[34]. The authors concluded that G-CSF could have an important function in

achieving positive pregnancy. In another, G-CSF is an integral part of the utero-placental cytokine network needed to establish and maintain pregnancy, at the maternal-foetal interface. Rahmat et al. indicated that the expression of G-CSF receptor was increased in endometrium, at the highest dose of rhG-CSF stimulation[35]. What's more, G-CSF and its receptor have been widely expressed in germ cells, such as placenta, endometrial epithelial cells, stromal cells and decidualized tissues, they play their biological roles by binding to G-CSF receptors[36].

With the increasing understanding of G-CSF in reproduction, the majority of researches on the mechanism of G-CSF began to emerge. The study indicated G-CSF seems able to influence endometrial expressions in implantation process involving endometrial vascular remodelling, local immune modulation and cellular adhesion pathways[35]. And G-CSF was reported to have positive effects on oocyte maturation and embryonic development[37]. Decidualization of endometrial stromal cells is one of the key factors for successful implantation. T.Tanaka and coworkers demonstrates that G-CSF enhances the decidualization process in ESCs[38]. Also G-CSF contributes to the improvement of the implantation by adding G-CSF into the cultural medium[39]. The present results suggest that G-CSF may play a significant role in follicular development[40]aid to embryo implantation.

For many decades, mounting evidence from studies in mice and humans supports the idea that G-CSF have positive effect in embryo implantation and pregnancy development. However, the specific target of G-CSF on endometrial cells is not clear. Clinicians must consider the patient's condition comprehensively and choose the appropriate time and dose to make the patients with RIF obtain better pregnancy outcomes.

Limitations

The limitation of our study is that it is a retrospective clinical analysis, and the control group is lack of strict matching(No saline infusion as control); And the number of patients aged between 20 and 29 in the study was very small, and no further hierarchical analysis was performed. Among the subjects we included ,2 cases were perfused 4 times and all obtained clinical pregnancy,.and there were 12 cases with 3 times of perfusion ,9 of which obtained clinical pregnancy. Although this study established that the number of perfusion times has a high degree of specificity in predicting the outcome of clinical pregnancy, the sample size of the intervention group was small, We need to be further confirmed by large sample, multi-center randomized controlled trials.

Declarations

Funding

The work described in this paper was supported by the National Natural Science Foundation of China (81960279) and (81401261), Gansu Province Science and Technology Fund (18JR3RA361), Chengguan District Science and technology project (2019SHFZ0026) and the Fund of the First Hospital of Lanzhou University (ldyyyn2018-55).

Author contributions

Meng Lyu Wrote the original draft and manuscript, ；Xiaoling Ma and JunpingHu collect and analyze data；JunpingHu and Hongjuan Zhan prepared figures 1-3 and table1-3; Lin Liu was responsible for the conception and revision of the manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare that they have nothing to dis-close.

Ethical approval

The project was approved and supervised by the Ethics Committee of the First Hospital of Lanzhou University.All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.This article does not contain any studies with animals performed by any of the authors. With waiver of informed consent due to the retrospective, observational design of the study, and the Ethics Committee of the First Hospital of Lanzhou University abandoned the informed consent procedure for the study

References

1. Scheffer JB, Scheffer BB, Carvalho RF, Aguiar AP, Lozano D, Labrosse J, Grynberg M. A comparison of the effects of three luteal phase support protocols with estrogen on in vitro fertilization-embryo transfer outcomes in patients on a GnRH antagonist protocol. JBRA Assist Reprod 2019; 23: 239–245.
2. Zhu X, Ye H, Fu Y. Duphaston and human menopausal gonadotropin protocol in normally ovulatory women undergoing controlled ovarian hyperstimulation during in vitro fertilization/intracytoplasmic sperm injection treatments in combination with embryo cryopreservation. Fertil Steril 2017; 108: 505–512.
3. Zeyneloglu H, Onalan G. Remedies for Recurrent Implantation Failure. Seminars in Reproductive Medicine 2014; 32: 297–305.
4. Sheikhansari G, Pourmoghadam Z, Danaii S, Mehdizadeh A, Yousefi M. Etiology and management of recurrent implantation failure: A focus on intra-uterine PBMC-therapy for RIF. Journal of Reproductive Immunology 2020; 139: 103121.
5. Hashimoto T, Koizumi M, Doshida M, Toya M, Sagara E, Oka N, Nakajo Y, Aono N, Igarashi H, Kyono K. Efficacy of the endometrial receptivity array for repeated implantation failure in Japan: A retrospective, two-centers study. Reprod Med Biol 2017; 16: 290–296.
6. Thomas J, Liu F, Link DC. Mechanisms of mobilization of hematopoietic progenitors with granulocyte colony-stimulating factor. Curr Opin Hematol 2002; 9: 183–189.
7. Tay J, Levesque JP, Winkler IG. Cellular players of hematopoietic stem cell mobilization in the bone marrow niche. Int J Hematol 2017; 105: 129–140.
8. Huang X, Liu Y, Bai S, Peng L, Zhang B, Lu H. Granulocyte colony stimulating factor therapy for stroke: A pairwise meta-analysis of randomized controlled trial. PloS one 2017; 12: e175774.
9. Miralaei S, Ashrafi M, Arabipoor A, Zolfaghari Z, Taghvaei S. The incidence rate of unresponsive thin endometrium in frozen embryo transfer cycles: A case-series of therapy with granulocyte colony stimulating factor. International Journal of Reproductive BioMedicine (IJRM) 2019.
10. Zeyneloglu HB, Tohma YA, Onalan G, Moran U. Granulocyte colony-stimulating factor for intracytoplasmic sperm injection patients with repeated implantation failure: which route is best?dagger. J Obstet Gynaecol 2020; 40: 526–530.
11. Eapen A, Joing M, Kwon P, Tong J, Maneta E, De Santo C, Mussai F, Lissauer D, Carter D, Eapen A, Joing M, Kwon P, Tong J, Carter D, Maneta E, De Santo C, Mussai F, Ahmed A, Bass C, Bender-Atik R, Bhattacharya R, Cheong Y, Dawood F, Granne I, Gupta P, Horne A, Manda P, Mohiyiddeen L, Moore J, Quenby S, Rai R, Shillito J, Stewart J, Truchanowicz E, Dwyer L, Small R, Sharpe L, Smith A, Lissauer D, Coomarasamy A. Recombinant human granulocyte– colony stimulating factor in women with unexplained recurrent pregnancy losses: a randomized clinical trial. Human Reproduction 2019; 34: 424–432.
12. Kamath MS, Kirubakaran R, Sunkara SK. Granulocyte-colony stimulating factor administration for subfertile women undergoing assisted reproduction. Cochrane Database Syst Rev 2020; 1: D13226.
13. Jain S, Mahey R, Malhotra N, Kalaivani M, Sangeeta P, Bhatt A, Singh N, Kriplani A. Effect of Intrauterine Perfusion of Granulocyte Colony-stimulating Factor on Endometrial parameters and In Vitro Fertilization Outcome in Women Undergoing In Vitro Fertilization/Intracytoplasmic Sperm Injection Cycles: A Randomized Controlled Trial. J Hum Reprod Sci 2018; 11: 254–260.
14. Wurfel W, Santjohanser C, Hirv K, Buhl M, Meri O, Laubert I, von Hertwig I, Fiedler K, Krusmann J, Krusmann G. High pregnancy rates with administration of granulocyte colony-stimulating factor in ART-patients with repetitive implantation failure and lacking killer-cell immunglobulin-like receptors. Hum Reprod 2010; 25: 2151–2152, 2152.
15. Gleicher N, Vidali A, Barad DH. Successful treatment of unresponsive thin endometrium. Fertil Steril 2011; 95: 2113–2123.
16. Li Y, Pan P, Chen X, Li L, Li Y, Yang D. Granulocyte colony-stimulating factor administration for infertile women with thin endometrium in frozen embryo transfer program. Reprod Sci 2014; 21: 381–385.
17. Kunicki M, Łukaszuk K, Woclawek-Potocka I, Liss J, Kulwikowska P, Szczyptańska J. Evaluation of Granulocyte Colony-Stimulating Factor Effects on Treatment-Resistant Thin Endometrium in Women UndergoingIn Vitro Fertilization. BioMed Research International 2014; 2014: 1–5.
18. Gleicher N, Kim A, Michaeli T, Lee HJ, Shohat-Tal A, Lazzaroni E, Barad DH. A pilot cohort study of granulocyte colony-stimulating factor in the treatment of unresponsive thin endometrium resistant to standard therapies. Hum Reprod 2013; 28: 172–177.
19. Lee D, Jo JD, Kim SK, Jee BC, Kim SH. The efficacy of intrauterine instillation of granulocyte colony-stimulating factor in infertile women with a thin endometrium: A pilot study. Clinical and Experimental Reproductive Medicine 2016; 43: 240.
20. Eftekhar M, Sayadi M, Arabjahvani F. Transvaginal perfusion of G-CSF for infertile women with thin endometrium in frozen ET program: A non-randomized clinical trial. Iran J Reprod Med 2014; 12: 661–666.
21. Jain S, Mahey R, Malhotra N, Kalaivani M, Sangeeta P, Bhatt A, Singh N, Kriplani A. Effect of intrauterine perfusion of granulocyte colony-stimulating factor on endometrial parameters and In Vitro fertilization outcome in women undergoing In Vitro fertilization/intracytoplasmic sperm injection cycles: A randomized controlled trial. Journal of Human Reproductive Sciences 2018; 11: 254.
22. Simon A, Laufer N. Assessment and treatment of repeated implantation failure (RIF). J Assist Reprod Genet 2012; 29: 1227–1239.
23. Davari-Tanha F, Shahrokh TE, Ghazi M, Shahraki Z. The role of G-CSF in recurrent implantation failure: A randomized double blind placebo control trial. Int J Reprod Biomed (Yazd) 2016; 14: 737–742.
24. Eftekhar M, Miraj S, Farid MM, Neghab N. Efficacy of Intrauterine infusion of granulocyte colony stimulating factor on patients with history of implantation failure: A randomized control trial. Int J Reprod Biomed (Yazd) 2016; 14: 687–690.
25. Kalem Z, Namli Kalem M, Bakirarar B, Kent E, Makrigiannakis A, Gurgan T. Intrauterine G-CSF Administration in Recurrent Implantation Failure (RIF): An Rct. Scientific Reports 2020; 10.
26. Aleyasin A, Abediasl Z, Nazari A, Sheikh M. Granulocyte colony-stimulating factor in repeated IVF failure, a randomized trial. Reproduction 2016; 151: 637–642.
27. Arefi S, Fazeli E, Esfahani M, Borhani N, Yamini N, Hosseini A, Farifteh F. Granulocyte-colony stimulating factor may improve pregnancy outcome in patients with history of unexplained recurrent implantation failure: An RCT. Int J Reprod Biomed (Yazd) 2018; 16: 299–304.
28. Zhang L, Xu W, Fu X, Huang Q, Guo X, Zhang L, Li S, Zhu J, Shu J. Therapeutic role of granulocyte colony-stimulating factor (G-CSF) for infertile women under in vitro fertilization and embryo transfer (IVF-ET) treatment: a meta-analysis. Archives of Gynecology and Obstetrics 2018; 298: 861–871.
29. Aleyasin A, Abediasl Z, Nazari A, Sheikh M. Granulocyte colony-stimulating factor in repeated IVF failure, a randomized trial. Reproduction (Cambridge, England) 2016; 151: 637–642.
30. Eftekhar M, Hosseinisadat R, Baradaran R, Naghshineh E. Effect of granulocyte colony stimulating factor (G-CSF) on IVF outcomes in infertile women: An RCT. Int J Reprod Biomed (Yazd) 2016; 14: 341–346.
31. Xie Y, Zhang T, Tian Z, Zhang J, Wang W, Zhang H, Zeng Y, Ou J, Yang Y. Efficacy of intrauterine perfusion of granulocyte colony-stimulating factor (G-CSF) for Infertile women with thin endometrium: A systematic review and meta-analysis. American Journal of Reproductive Immunology 2017; 78: e12701.
32. Kunicki M, Lukaszuk K, Woclawek-Potocka I, Liss J, Kulwikowska P, Szczyptanska J. Evaluation of granulocyte colony-stimulating factor effects on treatment-resistant thin endometrium in women undergoing in vitro fertilization. Biomed Res Int 2014; 2014: 913235.
33. Salmassi A, Schmutzler AG, Schaefer S, Koch K, Hedderich J, Jonat W, Mettler L. Is granulocyte colony-stimulating factor level predictive for human IVF outcome? Hum Reprod 2005; 20: 2434–2440.
34. Makinoda S, Hirosaki N, Waseda T, Tomizawa H, Fujii R. Granulocyte colony-stimulating factor (G-CSF) in the mechanism of human ovulation and its clinical usefulness. Curr Med Chem 2008; 15: 604–613.
35. Rahmati M, Petitbarat M, Dubanchet S, Bensussan A, Chaouat G, Ledee N. Granulocyte-Colony Stimulating Factor related pathways tested on an endometrial ex-vivo model. PLoS One 2014; 9: e102286.
36. McCracken S, Layton JE, Shorter SC, Starkey PM, Barlow DH, Mardon HJ. Expression of granulocyte-colony stimulating factor and its receptor is regulated during the development of the human placenta. J Endocrinol 1996; 149: 249–258.
37. Wurfel W. Treatment with granulocyte colony-stimulating factor in patients with repetitive implantation failures and/or recurrent spontaneous abortions. J Reprod Immunol 2015; 108: 123–135.
38. Tanaka T, Miyama M, Masuda M, Mizuno K, Sakamoto T, Umesaki N, Ogita S. Production and physiological function of granulocyte colony-stimulating factor in non-pregnant human endometrial stromal cells. Gynecol Endocrinol 2000; 14: 399–404.
39. Tevkin S, Lokshin V, Shishimorova M, Polumiskov V. The frequency of clinical pregnancy and implantation rate after cultivation of embryos in a medium with granulocyte macrophage colony-stimulating factor (GM-CSF) in patients with preceding failed attempts of ART. Gynecological Endocrinology 2014; 30: 9–12.
40. Wang H, Wen Y, Polan ML, Boostanfar R, Feinman M, Behr B. Exogenous granulocyte-macrophage colony-stimulating factor promotes follicular development in the newborn rat in vivo. Hum Reprod 2005; 20: 2749–2756.