Predictors of clinical pregnancy (CP) after elective single embryo transfer (eSBT)

Abstract

OBJECTIVE: To identify clinical, biochemical, or embryologic factors associated with the establishment of a clinical pregnancy following the eSBT.DESIGN: Retrospective cohort.MATERIALS AND METHODS: First cycles of IVF where eSBT was performed from 01/06 to 12/09 were used. Inclusion criteria were age < 38 and FSH levels < 10. Patients requesting eSBT with at least 3 eight-cell embryos, grade 1 or 2 three days after oocyte retrieval had eSBT. CP was defined as fetal heart motion at 7-8 weeks. Multivariate regression modeling was performed to identify predictors of clinical pregnancy.RESULTS: Patients meeting inclusion criteria (n=99) were identified and 66 had a CP (66.7%). Factors not associated with CP included age (mean 32.4), BMI (mean 24.1 kg/m2), and infertility diagnosis (anovulation 14%, endometriosis 11%, male 23%, tubal 16%, unexplained 28%, other 7%), or day 3 FSH (mean 6.2 mIU/mL). There was a significant association of days of stimulation with CP on multivariate regression modeling (OR = 0.582, CI 0.370-0.916, p=0.02) with longer stimulation resulting in lower CP. This association reached maximum benefit at 9 days of stimulation. Although stimulation protocol did not affect CP, GnRH agonist (GnRHa) trigger for oocyte maturation was negatively associated with CP in multivariate regression modeling (OR = 0.069, CI 0.020-0.239, p< 0.01). In antagonist cycles, hCG trigger resulted in higher CP (45/54, 83.3%) than GnRHa trigger (6/22, 27.3%). Oocyte and embryo parameters failing to affect CP included % mature, germinal vesicle, degenerate, or dark/grainy oocytes, multinucleated embryos on day 2, embryos compacted on day 3; and day 3 embryo grading of blastocyst replaced, # of embryos 7 cell grade I-IV or greater, or # of cryopreserved embryos.CONCLUSION: In this group of patients, prolonged ovarian stimulation is predictive of lower success of eSBT. While antagonist cycles did not result in lower CP, utilization of GnRH-a to trigger oocyte maturation has a significantly negative impact on CP. OBJECTIVE: To identify clinical, biochemical, or embryologic factors associated with the establishment of a clinical pregnancy following the eSBT. DESIGN: Retrospective cohort. MATERIALS AND METHODS: First cycles of IVF where eSBT was performed from 01/06 to 12/09 were used. Inclusion criteria were age < 38 and FSH levels < 10. Patients requesting eSBT with at least 3 eight-cell embryos, grade 1 or 2 three days after oocyte retrieval had eSBT. CP was defined as fetal heart motion at 7-8 weeks. Multivariate regression modeling was performed to identify predictors of clinical pregnancy. RESULTS: Patients meeting inclusion criteria (n=99) were identified and 66 had a CP (66.7%). Factors not associated with CP included age (mean 32.4), BMI (mean 24.1 kg/m2), and infertility diagnosis (anovulation 14%, endometriosis 11%, male 23%, tubal 16%, unexplained 28%, other 7%), or day 3 FSH (mean 6.2 mIU/mL). There was a significant association of days of stimulation with CP on multivariate regression modeling (OR = 0.582, CI 0.370-0.916, p=0.02) with longer stimulation resulting in lower CP. This association reached maximum benefit at 9 days of stimulation. Although stimulation protocol did not affect CP, GnRH agonist (GnRHa) trigger for oocyte maturation was negatively associated with CP in multivariate regression modeling (OR = 0.069, CI 0.020-0.239, p< 0.01). In antagonist cycles, hCG trigger resulted in higher CP (45/54, 83.3%) than GnRHa trigger (6/22, 27.3%). Oocyte and embryo parameters failing to affect CP included % mature, germinal vesicle, degenerate, or dark/grainy oocytes, multinucleated embryos on day 2, embryos compacted on day 3; and day 3 embryo grading of blastocyst replaced, # of embryos 7 cell grade I-IV or greater, or # of cryopreserved embryos. CONCLUSION: In this group of patients, prolonged ovarian stimulation is predictive of lower success of eSBT. While antagonist cycles did not result in lower CP, utilization of GnRH-a to trigger oocyte maturation has a significantly negative impact on CP.