Role of Aromatase Inhibitor to Enhance Ovulation in Poor Responder during Induction with Short Antagonist Protocol in Cases of Intracytoplasmic Sperm Injection
Objective: Study the effect of aromataze inhibitor with short antagonist protocol to enhance ovulation response in patients expected to be poor responder undergoing ICSI.
Methodology: A prospective clinical trial included all patients expected to have poor ovulation response during ovarian stimulation for ICSI. Conducted in Maternity Hospital IVF unite and two tertiary referral infertility private clinics associated with the reproductive sciences division. 50 patients were enrolled in the study divided randomly into two groups. Study group patients were offered letrozole, 2.5 mg/day from day 1-5 of the menstrual cycle with HMG300 IU/day starting on first day of the cycle with follow up by Trans vaginal ultrasound (TVUS) when at least three follicles reach 14mm diameter, GnRh antagonist given 0.25 mg SC injection daily till the day of hCG injection. HCG (10,000 IU) was given when at least three leading follicles were 18mm followed by ovum pick up. Control group offered the same management without letrozole.
Main Outcome Measures: Primary outcome measure: Number of follicles reaches more than 18mm and number of metaphase II oocytes. Secondary outcome measure: clinical pregnancy rate.
Results: Improved response to HMG stimulation with letrozole co-treatment was evidenced by significant number of follicles measuring more than 18mm (5.3 ± 3.5.in the study group versus 3.9 ± 1.9 in control group (p value 0.003). The number of metaphase II oocytes was significantly higher in the study group (4.6 ± 2.4 Versus3.3 ± 0.6). During letrozole co treatment clinical pregnancy was achieved in (20%) of cases.
Conclusion: We demonstrated a good benefit of aromatase inhibitors for improving ovarian response to HMG in short antagonist protocol in patients expected to be poor responders.