Correlation of serum estradiol level on the day of ovulation trigger with the reproductive outcome of intracytoplasmic sperm injection.

Background: Serum estradiol (E2) levels are measured in in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI), to assess the ovarian response and to predict ovarian hyperstimulation syndrome. The impact of peak E2 levels on IVF-ICSI outcome was found to be inconsistent in the previous studies.

Aim: To evaluate the impact of the serum E2 levels on the day of ovulation trigger with the reproductive outcome of ICSI.

Settings And Design: Retrospective observational study. ART Center, at a Tertiary Care University Teaching Hospital.

Subjects And Methods: Eighty-nine infertile women, who underwent ICSI with fresh embryo transfer over a period of 3 years, were included in the study. The study subjects were grouped based on the serum E2 level on the day of ovulation trigger:- Group I - <1000 pg/ml, Group II - 1000-2000 pg/ml, Group III - 2000.1-3000 pg/ml, Group IV - 3000.1-4000 pg/ml, and Group V >4000 pg/ml. The baseline characteristics and controlled ovarian hyperstimulation (COH) outcome were compared among the study groups.

Statistical Analysis Used: Chi-square test, Student's t-test, ANOVA, and logistic regression analysis.

Results: The study groups were comparable with regard to age, body mass index, ovarian reserve. Group V had significantly higher number of oocytes retrieved than I and II (18.90 vs. 11.36 and 11.33; P = 0.009). Group IV showed significantly higher fertilization rate than I, III, and V; (92.23 vs. 77.43, 75.52, 75.73; P = 0.028). There were no significant differences in the implantation rates (P = 0.368) and pregnancy rates (P = 0.368).

Conclusion: Higher E2 levels on the day of ovulation trigger would predict increased oocyte yield after COH. E2 levels in the range of 3000-4000 pg/ml would probably predict increased fertilization and pregnancies in ICSI cycles.