The Effect of Prolongated Time to Achieve Ovarian Suppression Before Start of Stimulation on Pregnancy Rates in ART Cycles

Abstract

Objective: To determine if the prolonged time for achieving ovarian suppression before starting stimulation affected the pregnancy rates. Patients and Methods: Retrospective cohort analysis was performed on 565 women undergoing first assisted reproductive technologies (ART) treatment in a University-affiliated Hospital. The women were grouped according to the duration of downregulation by gonadotropin-releasing hormone (GnRH) analogue. Group A consisted of women in the lower 25th percentile, group B consisted of women in the upper 25th percentile, according to the duration of GnRH analogue use. The implantation and clinical pregnancy rates were compared. Results: Mean number of aspirated and inseminated oocytes were more in group A than in group B. Implantation rates were similar. Clinical pregnancy rates were alike. Conclusion: Prolonged time for achieving ovarian supression does not compromise clinical pregnancy rates in ART cycles.

Does the quality of an embryo differ between long down-regulated and antagonist cycles among age and cycle day 3 FSH-matched women undergoing art?

“…Since day 3 embryos with more than 6 cells and the average scores of embryos transfered at cleavage stage were comparable in both groups, similar pregnancy rates would have been expected. Comparison of implantation rates between different protocols have led to the belief that the beneficial effects of GnRH analogues were related to an improved endometrial receptivity [14]. However, a direct action of GnRH analogue on the endometrium remains speculative.…”

“…For the long protocols, pituitary desensitization was achieved by s.c. administration of leuprolide acetate (1 mg/ mL; Lucrin flacon , Abbott) during the luteal phase of the cycle preceding before the start of gonadotropin stimulation [14]. When adequate down regulation had been achieved (endometrial thickness <4 mm or serum estradiol <50 pg/ ml), usually after at least 10 days of leuprolide acetate administration, controlled ovarian hyperstimulation was accomplished with s.c. administration of recombinant FSH (Gonal-F, Follitropin alpha; Merck-Serono Inc.), at a starting dose of 300 IU per day.…”