Low concentration of hyaluronidase for oocyte denudation can improve fertilization rates and embryo quality.

OBJECTIVE: Hyaluronidase enzyme is an extremely important factor for the process of oocyte denudation, but little is known about its negative effects. METHODS: This prospective randomized study analyzed the results of using different concentrations of hyaluronidase (Diluted: 8IU/mL and Normal: 80IU/mL) used for denudation of sibling-oocytes for 22 women undergoing treatment for assisted reproduction by ICSI. A total of 192 oocytes were injected, being 104 for group I (diluted) and 88 for group II (normal). We analyzed fertilization rate, cleavage, embryo quality at 48 and 72 hours and number of transferred embryos in each group. RESULTS: The diluted enzyme group showed better results in fertilization rates (92.3% vs. 80.6%), mean cleavage (4.18 ± 2.57 vs. 3.09 ± 1.90), in 48-hour embryos A and A + B (60.9% vs. 44.1% and 90.2% vs. 82.3%) and at 72 hours (45.6% vs. 36.8% and 77.1% vs 66.2%), and number of embryos selected for transfer (61.8% vs. 38.1%). The overall pregnancy rate was 59.1%. CONCLUSION: This study demonstrates that the use of 8 IU/mL of hyaluronidase, according to the following protocol, is beneficial and can be successfully used for oocyte denudation, and it is also economically advantageous to the laboratory.

Evaluation of results obtained with corifollitropin alfa after poor ovarian response in previous cycle using recombinant follicular stimulating hormone in the long-term protocol.

OBJECTIVE: This study evaluated the use of Corifollitropin alfa in patients with previous poor response to recombinant follicle stimulating hormone in long-term protocols using gonadotropin-releasing hormone. METHODS: Twenty-seven poor responders to previous treatment with the long term protocol using the recombinant follicle stimulating hormone (Group 1) were selected and then submitted to a second attempt using the same long term protocol with Corifollitropin alfa instead of the recombinant follicle stimulating hormone (Group 2).Ovarian down-regulation was achieved using subcutaneous administration of Leuprolide Acetate. Ovarian stimulation was performed with recombinant follicle stimulating hormone until the administration of human chorionic gonadotropin, followed by follicular aspiration (Group 1). Group 2 was submitted to this same protocol using Corifollitropin alfa instead of recombinant follicle stimulating hormone. RESULTS: There were significant differences in the number of aspirated oocytes, percentage of mature oocytes, amount of injected oocytes and transferred embryos - with all of these parameters being increased in the Corifollitropin alfa group. In addition, the rates of pregnancy and ongoing pregnancy were also significantly higher in the Corifollitropin alfa group. CONCLUSION: The present study demonstrated that the use of Corifollitropin alfa in the long-term protocol could be a highly effective alternative for patients with poor ovarian response, who were unsuccessful in a previous treatment with In Vitro Fertilization - Intracytoplasmic Sperm Injection.