RESUMO
BACKGROUND: The use of frozen embryo transfer (FET) is increasing worldwide in the treatment of infertility by in vitro fertilization. Different methods of endometrial preparation for FET have been suggested. OBJECTIVE: The aim of this study was to compare the pregnancy outcomes after treatment with letrozole and those after treatment with the combination of gonadotropin-releasing hormone (GnRH) agonist and estradiol in FET. MATERIALS AND METHODS: This randomized controlled trial study was conducted on 142 infertile women with a history of previous FET failure. Participants were randomly assigned to two groups (n = 71 each). The GnRH group received 500 µg of buserelin plus 4mg estradiol (which increased to 8 mg if endometrial thickness was less than 5 mm), and the letrozole group received 5 mg of letrozole plus 75 IU of recombinant human follicle-stimulating hormone). At least two high-quality embryos were transferred to each subject in both groups. The outcome measures were clinical pregnancy rate and fetal heart rate detection. RESULTS: Subjects in the study groups had similar demographic characteristics and baseline clinical condition. Mean endometrial thickness in the letrozole and GnRH agonist groups were 8.90 ± 0.88 mm and 8.99 ± 0.85 mm, respectively (p = 0.57). The number of positive results of the beta human chorionic gonadotropin test and detection of fetal heartbeat were not significantly different between the groups (p > 0.05). CONCLUSION: The administration of letrozole and GnRH may produce similar pregnancy outcomes in FET.
RESUMO
BACKGROUND: In this work, we have determined the levels of interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-α), which function as cytokines in endometrial receptivity, through the endometrial secretion within the eligible individuals and thus studied their relationships with the success or failure of pregnancy in in vitro fertilization/intra cytoplasmic sperm injection (IVF/ICSI) cycles. MATERIALS AND METHODS: In this prospective study, 76 women were selected for their first IVF/ICSI and met the study inclusion criteria. All of the patients have undergone the endometrial secretion aspiration prior to performing the oocyte collection. The levels of IL-1and TNF-α were analyzed by the means of enzyme-linked immunosorbent assay method, using special standard kits. The patients were requested to undergo the serum human chorionic gonadotropin measurements and ultrasound evaluation for the purpose of detecting successful implantations and pregnancies. RESULTS: Among the 76 subjects of the study, 33 (43.4%) patients had a positive beta-human chorionic gonadotropin (ß-hCG) and 44 (56.6%) resulted in a negative ß-hCG. It should be also noted that through the patients with positive ß-hCG, 23 (30.3%) of them displayed fetal heart rate in their transvaginal sonography (TVS). Compared to the group with failed pregnancies and their cytokine levels, we perceived a higher concentration of IL-1 in the group containing successful chemical pregnancies (P=0.00). However, there was no significant difference in terms of clinical pregnancy in the IL-1 levels between the two groups (P=0.06). In addition, there was not any notable difference in the levels of TNF-α between the two groups, neither in terms of chemical nor clinical pregnancy (P=0.8 and P=0.6, respectively). CONCLUSION: The current study suggests that higher concentrations of IL-1 in endometrial secretions could be associated with improved endometrial receptivity and IVF outcome. With regards to TNF-α, no statistically significant difference was observed between the groups of with and without successful pregnancies.
