Objective: To determine whether the use of GnRH antagonist in cycles converted from ovulation induction-IUI to IVF affects cycle outcome and pregnancy rates.
Design: Retrospective cohort study.
Setting: Academic research institution.
Patient(s): One hundred eighty-two consecutive patients with ovulation induction-IUI to IVF conversions undergoing oocyte retrieval conducted at our institution from 2004 to 2006.
Intervention(s): The relation between observation of fetal heartbeat and GnRH antagonist exposure was evaluated with use of multivariable logistic regression. The difference in intermediate cycle outcomes by antagonist exposure was estimated with use of linear regression.
Main outcome measure(s): Fetal cardiac activity on early ultrasound, intermediate cycle parameters.
Result(s): For patients given treatment with a GnRH antagonist, the odds ratio for achieving pregnancy was 2.13 (95% confidence interval = 1.03-4.39) compared with untreated patients, independent of age and E(2) levels on day of hCG. Patients given antagonist had 1.6 more follicles and 2.1 more oocytes retrieved, 1.9 more mature oocytes, and 2.3 more fertilized oocytes, and the fertilization rate was 9.7% higher.
Conclusion(s): Gonadotropin-releasing hormone antagonist use in ovulation induction-IUI to IVF conversions was associated with increased pregnancy rates and improved intermediate cycle parameters, controlled for age and E(2) levels on day of hCG. Addition of a GnRH antagonist should be considered in ovulation induction-IUI to IVF conversions.
Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.