The effect of intrauterine hCG injection before embryo transfer on pregnancy rate in frozen embryo transfer cycles

Objective: HCG (human chorionic gonadotropin), which is secreted by cytotrophoblast cells, plays an important role in improving pregnancy outcomes among patients with infertility or related problems. In this study, we evaluate the effect of intrauterine hCG injection prior to frozen embryo transfer on pregnancy outcomes. Methods: In this clinical trial study, among women with infertility problems referred to (XXX) and those with frozen embryos were included in the study. 155 patients in the intervention group received 500 units of hCG while 157 in control group received saline prior to embryo transfer. Along with demographic data, successful in vitro fertilization and clinical pregnancy, loss of pregnancy, successful transplantation, and biochemical parameters were compared among the two groups. Results: The mean age of the patients included in the study was 32.97 ± 3.31 years. The level of anti-Mullerian hormone, follicle stimulating hormone and the grade of frozen embryos were not significantly different between the two groups (P > 0.05). The rate of laboratory pregnancy in the intervention group was significantly higher than in the control group (51 vs 35), p = 0.006. The rate of successful implantation and clinical pregnancy in the intervention group was also significantly higher, p = 0.01 and p = 0.006, respectively. Overall loss of pregnancy in intervention group was 78.1 and 86.0 in control group which was not significantly different, p = 0.068. Conclusion: The outcomes of our study showed that 500 IU of hCG prior to embryo transfer improves the rate of clinical and laboratory pregnancy. However, it does not reduce the rate of loss of pregnancy. Further studies are therefore required in this area. © 2022 The Author