Asian ethnicity is associated with reduced pregnancy outcomes after IVF using a downregulated GnRH agonist suppression protocol

Abstract

OBJECTIVE: We have previously shown Asian women have significantly fewer pregnancies than Caucasian women when undergoing IVF (OR 0.69, CI 0.49,0.99). Similarly, SART data have corroborated these findings at a national level. However, these data included patients with varying prognoses utilizing multiple different simulation protocols. By restricting this analysis to those undergoing downregulated GnRH protocol, we aimed to determine if these differences existed in patients with presumed good prognosis. DESIGN: Cross-sectional analysis and multivariate modeling. MATERIALS AND METHODS: Self-identified Caucasian and Asian women undergoing a long agonist stimulation protocol between 2002 and 2006 were included in the analyses. The main outcome was clinical pregnancy defined as fetal heart motion by ultrasound. Univariate analyses were performed to determine baseline characteristic differences between the Asian population and the Caucasian population. To estimate the independent contribution of Asian ethnicity, multivariable logistic regression analyses were performed. A backward conditional elimination was used to generate the most parsimonious model, using p=0.20. The final model included ethnicity, age, diagnosis of endometriosis, AFC, and day 3 FSH (Table 1). RESULTS: Five hundred thirty-one Caucasian women and 294 Asian women underwent long agonist stimulation as their first IVF cycle at UCSF from 2002-06. There were no significant differences in baseline characteristics. Peak estradiol levels were significantly higher in Asian women (p<0.001). Regression analyses yielded an unadjusted OR of achieving clinical pregnancy for Asian women of 0.62 (95% CI 0.46,0.83) when compared to Caucasian women, and an adjusted OR of 0.56 (95% CI 0.40,0.78). CONCLUSIONS: Asian ethnicity is an independent predictor of poor IVF outcome in patients undergoing downregulated agonist suppression protocol for their first cycle of IVF. The persistent difference in pregnancy outcomes despite a presumed good prognosis suggests that the effect may be mediated by factors not currently defined in clinical practice.Table 1Asian (n=294)Caucasian (n=531)p valueAge36.4 +/- 4.036.7 +/- 4.0NSNulligravid53.9%55.1%NSMale Factor Diagnosis43.2%41.8%NSDay 3 FSH7.2 +/- 3.27.2 +/- 3.2NSAFC9.9 +/-6.89.7 +/-6.8NSPeak Estradiol2591.9 +/- 14472302.4 +/- 1371p=0.0002Embryo Transfer Number2.9 +/- 1.33.0 +/- 1.4NSClinical Pregnancy Rate35.5%45.6%p=0.0003Delivery Rate28.1%38.7%p=0.0001 Open table in a new tab