Impact of GnRH analogues on oocyte/embryo quality and embryo development in in vitro fertilization/intracytoplasmic sperm injection cycles: a case control study

<p>Abstract</p> <p>Background</p> <p>Despite the clinical outcomes of ovarian stimulation with either GnRH-agonist or GnRH-antagonist analogues for in vitro fertilization (IVF) being well analysed, the effect of analogues on oocyte/embryo quality and embryo development is still not known in detail. The aim of this case-control study was to compare the efficacy of a multiple-dose GnRH antagonist protocol with that of the GnRH agonist long protocol with a view to oocyte and embryo quality, embryo development and IVF treatment outcome.</p> <p>Methods</p> <p>Between October 2001 and December 2008, 100 patients were stimulated with human menopausal gonadotrophin (HMG) and GnRH antagonist in their first treatment cycle for IVF or intracytoplasmic sperm injection (ICSI). One hundred combined GnRH agonist + HMG (long protocol) cycles were matched to the GnRH antagonist + HMG cycles by age, BMI, baseline FSH levels and by cause of infertility. We determined the number and quality of retrieved oocytes, the rate of early-cleavage embryos, the morphology and development of embryos, as well as clinical pregnancy rates. Statistical analysis was performed using Wilcoxon's matched pairs rank sum test and McNemar's chi-square test. P < 0.05 was considered statistically significant.</p> <p>Results</p> <p>The rate of cytoplasmic abnormalities in retrieved oocytes was significantly higher with the use of GnRH antagonist than in GnRH agonist cycles (62.1% vs. 49.9%; P < 0.01). We observed lower rate of zygotes showing normal pronuclear morphology (49.3% vs. 58.0%; P < 0.01), and higher cell-number of preembryos on day 2 after fertilization (4.28 vs. 4.03; P < 0.01) with the use of GnRH antagonist analogues. The rate of mature oocytes, rate of presence of multinucleated blastomers, amount of fragmentation in embryos and rate of early-cleaved embryos was similar in the two groups. Clinical pregnancy rate per embryo transfer was lower in the antagonist group than in the agonist group (30.8% vs. 40.4%) although this difference did not reach statistical significance (P = 0.17).</p> <p>Conclusion</p> <p>Antagonist seemed to influence favourably some parameters of early embryo development dynamics, while other morphological parameters seemed not to be altered according to GnRH analogue used for ovarian stimulation in IVF cycles.</p

Impact of highly purified versus recombinant follicle stimulating hormone on oocyte quality and embryo development in intracytoplasmic sperm injection cycles

The quality of oocytes and developing embryos are the most relevant factors determining the success of an in vitro fertilization (IVF) treatment. However, there are very few studies analyzing the effects of different gonadotrophin preparations on oocyte and embryo quality. A retrospective secondary analysis of data collected from a prospective randomized study was performed to compare highly purified versus recombinant follicle stimulating hormone (HP-FSH vs. rFSH). The main outcome measures were quantity and quality of oocytes and embryos, dynamics of embryo development, cryopreservation, clinical pregnancy and live birth rate. The number of retrieved and of mature (MII) oocytes showed no significant differences. Fertilization rate was significantly higher in the HP-FSH group (68.9% vs. 59.9%, p = 0.01). We also found significantly higher rate of cryopreserved embryos per all retrieved oocytes (23.4% vs. 14.5%, p = 0.002) in the HP-FSH group. There were no significant differences in clinical pregnancy and in live birth rates. Oocytes obtained with HP-FSH stimulation showed higher fertilisability, whereas pregnancy and live birth rates did not differ between the groups. However, patients treated with HP-FSH may benefit from the higher rate of embryos capable for cryopreservation, suggesting that cumulative pregnancy rates might be higher in this group

Importance of cytoplasmic granularity of human oocytes in In vitro fertilization treatments

The aim of this study was to examine the effect of different stimulation protocols on oocyte granularity and to determine the influence of cytoplasmic granularity on further embryo development. A total of 2448 oocytes from 393 intracytoplasmic sperm injection (ICSI) cycles were analysed retrospectively. Oocytes were classified into 5 groups according to cytoplasmic granularity. (A) no granule or 1–2 small (5 μm); (D) refractile body; (E) dense centrally located granular area. Correlation between characteristics of hormonal stimulation, oocyte granularity and embryo development was analysed. The occurrence of cytoplasmic granularity was influenced by the patient’s age and characteristics of stimulation. The type of granulation had no effect on fertilization rate and zygote morphology. However, some type of granulation resulted in a lower cleavage rate and more fragmented embryos. Our results provided additional information on how hormonal stimulation affects oocyte quality. While cytoplasmic granularity seems not to have an effect on fertilization and embryo development, the presence of refractile body in the oocyte is associated with reduced cleavage rates and impaired embryo development

Correlation between first polar body morphology and further embryo development

First polar body (PB) morphology of human oocytes can indicate further embryo development and viability. However, controversial data have been published in this topic. Our retrospective study analyses the fertilization and further development of oocytes in relation to different morphological features of the first PB. The morphology of 3387 MII oocytes from 522 in vitro fertilization (IVF) treatments were assessed before intracytoplasmic sperm injection (ICSI). Oocytes were classified according to their first PB morphology. Assessment of fertilization and embryonic development (cell number, embryo grade, amount of anuclear fragmentation and presence of multinucleated blastomeres) was performed 16-20 and 42-48 hours after ICSI. Our results show that fertilization rate and embryo quality is influenced by PB morphology, while speed of development is not affected by the morphology of the first PB. Contrary to previous findings, our results suggest that oocytes with a fragmented PB had a higher developmental ability than those with an intact PB. However, we observed a lower viability of oocytes with a large PB. Since there are contradictions in this and previous observations, an extensive study is needed with standard hormonal stimulation protocol and oocyte evaluation criteria