Regimen of ovarian stimulation affects oocyte and therefore embryo quality

Abstract

Without any doubt the regimen used to mature multiple capable oocytes for IVF impacts IVF outcomes. Studies have indicated that the inclusion of LH activity, adjuvant agents such as growth hormone (GH), and regimens providing for simultaneous action of both LH and FSH during final oocyte maturation may have beneficial effects on IVF outcomes. Because of the difficulty in improving IVF outcomes in poor responders, the studies on GH are of particular interest. As pointed out in this review, the apparent beneficial effects of GH on oocyte competence may also apply to older women or to normal responders with reduced embryo quality. A much more difficult question is whether and how much ovarian stimulation impacts on oocyte competence. Paradoxically it seems that there are not demonstrated differences between the stimulated and the natural unstimulated cycle, whereas studies in laboratory animals and IVF patients have shown deleterious effects of higher compared with lower doses of gonadotropins. Recent studies suggest that the use of high doses of gonadotropins as an independent factor correlates negatively with the probability of live birth, whereas a high ovarian response per se is associated with better cumulative pregnancy rates, owing to the availability of more euploid and good-quality embryos. Although adjunctive use of androgens has not been discussed here, it is briefly covered in the first review of this series.

Cumulative live birth rate and cost-effectiveness analysis between GnRH-antagonist protocol and multiple minimal ovarian stimulation in poor responder

“…Reports indicated that higher dose of gonadotropins resulted in increasing rate of aneuploidy in embryos and granulosa cells [25]. But there are some controversies about that.…”

Oxidation of Sperm Nucleus in Mammals: A Physiological Necessity to Some Extent with Adverse Impacts on Oocyte and Offspring

“…This oocyte-driven DNA repair process underlines the importance of oocyte quality in preventing transmission of paternal DNA alterations into the embryo. Whenever the oocyte's ability to repair is reduced (e.g., due to maternal age or non-physiological pressure linked to forced oocyte production following hormonal stimulation during the course of ART IVF procedures [35]), there is a risk that unrepaired oxidized residues remain in the paternal pronucleus. If the oocyte BER pathway is not fully effective, and/or if the level of oxidized bases in the sperm nucleus is too high to be treated properly, this will result in nonrepair and/or false repair leading to mainly transversion-type mutations (following Hoogsteen base pairing between 8-OHdG and adenine [36]) that will ultimately be transmitted to the developing embryo and future generations [37].…”

Electroacupuncture Enhances Number of Mature Oocytes and Fertility Rates forIn VitroFertilization

“…However, this multifollicle development will occur in various amounts and functional activities, so that it contains oocytes at various maturation stages. 8 Storage of maternal messenger RNA (mRNA) accumulated during folliculogenesis and exogenous gonadotropin administration accelerates nucleation maturation, which results in insufficient storage of mRNA, resulting in low oocyte and embryo-development quality. 9 As a minimal risk therapy-and one that does not cause serious side-effects-in recent years, acupuncture has also been widely used as a complementary therapy in IVF programs.…”