The Use Of Oxytocin Antagonist In Repeated Implantation Failure

Background For women treated with in vitro fertilization-embryo transfer, more than one harf of them may undergo embryo freezing and frozen embryo transfer(FET), which has been a common technique of ART. FET improves the implantation and pregnancy rate of infertility patients, but some remains unsuccessful. Many factors influence the results of FET, such as ages, function of ovaries, as well as the failed numbers before. Repeated implantation failure(RIF)has been one of the most difficult problems in ART. The causes of RIF can be attributed to uterine, genetic, embryonic or other causes, in another words, the causes are not clear. The general definition of RIF is failures to conceive after two or more unsuccessful embryo transfer cycles or total number of the embryos with good quality achieves10or more. A patient of RIF conceived successfully after adopting of atosiban to reduce her frequency of uterine contractions in2007. This case remaindered that abnormal frequency of uterine might be a cause of RIF. Atosiban, the mixed oxytocin and vasopressin receptor antagonist, has been trying to treat patients of RIF.Objective PART ONE:This part aimed to analyze factors that influence the live birth rate in FET cycle. PART TWO:The research aimed to investigate the use of atosiban in improving the implantation rate and clinical pregnancy rate in FET patients with RIF. PART THREE:This part examined the frequency of uterine contraction in patients with RIF and compared the frequency between atosiban adopting patients and nothing adopting patient. It tried to state the function of atosiban to uterine endometrium.Materials and Methods PART ONE:A total of2163cycles undergoing FET in Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from2012.1to2012.12was involved in the study. The live birth was used to define the final outcome. We analyzed factors such as ages, years of infertility, BMI, serum FSH, basal antral follicle counts, failure cycle numbers, total numbers of embryo transfer and numbers of good-quality embryo transfer of patients in live-birth group and non-live-birth group to show if they had significant differences. Then we analyzed the different factors using logistic regression to summarize the risk factors or the protective factors, furthermore the independent risk or protective factors. PART TWO:This study enrolled188patients with RIF undergoing FET and they were randomly divided into two groups following admittance and exclusion criterions. Patients in atosiban group were injected atosiban6.75mg before embryo transfer while patients in anther group were not. The implantation rate and clinical pregnancy rate in two groups were compared. PART THREE:A total number of44patients were involved and divided into two groups using the same criterions as part two. The examinination of frequency of uterine contractions was performed twice in atosiban group, before and after the injection of atosiban. For the patients in control group, we examine their uterine contractions just at the same time with atosiban group except the adoption of atosiban. Then we compared the frequency of uterine contractions of patients in the two groups to conform the effect of atosiban.Results PART ONE:Logistic regression showed women’s ages, years of infertility, BMI, AFC, failed cycle numbers(≥2), thickness of endometrium, serum progesterone levels and numbers of good-quality embryo transfer were all factors affecting the live birth of FET (P<0.05).Moreover, AFC, thickness of endometrium and numbers of good-quality embryo transfer were the independent protective factors (B>0, OR>1) while women’s age, years of infertility, BMI, serum progesterone levels and failed cycle numbers(≥2) were the independent risk factors (B<0, OR<1). PART TWO:The characteristics of patients in two groups didn’t have significant differences (P>0.05).Patients in atosiban group experienced higher implantation rate and clinical pregnancy rate and lower miscarriage rate compared with control group (P<0.05). PART THREE:The frequency of uterine contractions reduced after injection of atosiban and reduced significantly in patients of atosiban group compared with those in control group.Conclusion PART ONE:The failed cycle numbers(>2) was the independent risk factors for live birth rate in FET which the confidence interval(CI)is [0.584,0.869]. PART TWO:Atosiban may improve the pregnancy outcomes of patients with RIF as it raises their implantation rate and clinical pregnancy rate and reduces miscarriage rate. PART THREE:Atosiban significantly reduced the frequency of uterine contractions of patients with RIF and though this effect atosiban may help to improve their pregnancy outcome.