The concept of an aged oocyte that is compromised in its developmental potential isĬonsistent with research performed in lactating dairy cows.
However, more recent work has not found this sameĬorrelation between increased LH concentrations and increased miscarriage rates/lower The cause for the increase in miscarriage. Ovulation of an “aged” oocyte that would have lower developmental competency and might be that this effect was due to an overstimulation of the oocyte, leading to In humans that embryos from oocyte donors with increased basal LH have a higher incidence ofĪbortion, and that oocyte fertilization ratesĪre decreased during IVF of patients with increased basal LH concentrations. Several earlier studies have shown that there is a positive correlation between preovulatoryĬirculating LH concentrations and miscarriage rate in human patients. (FSH) ratio, and altered LH pulse patterns are observed in PCOS patients. Oocyte development and maturation or possibly early embryo development, rather than duringĪlso noteworthy is the research that has shown that the incidence of increasedĬoncentrations of luteinizing hormone (LH), increased LH to follicle-stimulating hormone
That excessive exposure to insulin or insulin resistance is having negative impacts during In an increase in circulating insulin concentrations, led to oocytes that, after in vitroįertilization (IVF), exhibited reduced cleavage rates and embryonic development to the Additionally, overfeeding sheep for 8 weeks prior to oocyte collection, which resulted found that feeding an insulinogenic dietīefore and during a superovulatory protocol decreased early embryo quality in superovulatedĬows. Although serum insulin concentrations were not directly analyzed, a study by YaakubĮt al. Thus, there is some clinicalĮvidence that hyperinsulinemia can reduce reproductive efficiency in some circumstances.Īnimal studies also suggest an adverse effect of elevated insulin on oocyte and embryo Treatment with metformin, an insulin sensitizer often used to aid in the treatment of PCOS,Ĭan increase pregnancy and live birth rates in women undergoing ovulation induction with Meta-analyses of randomized -controlled trials indicate that Reported in women with PCOS and/or insulin resistance. Increased incidence of early pregnancy loss and reduced live birth rate has been In addition to these diagnostic features, there are metabolicĪbnormalities associated with this syndrome, such as hyperinsulinemia and insulin ĭiagnosis is based on the presence of hyperandrogenaemia, polycystic ovaries, and/or Population, depending on diagnostic criteria. Heterogenous reproductive disorder that has been estimated to affect up to 15% of the female For example, in women, polycystic ovarian syndrome (PCOS) is a There are results from studies of humans and other mammals indicating that hyperinsulinemiaĪnd insulin resistance can produce detrimental effects on ovulation, fertilization, andĮmbryo development. These results indicate that acute elevation in insulin during the preovulatoryįollicular wave can decrease percentage of large follicles that ovulate, particularly whenĬombined with increased LH, and reduce fertilization of ovulated oocytes. Were degenerate, quality 1, or quality 1 and 2 of total structures collected or fertilized There was no effect ofĮither PROP or LH on any measure of embryo quality including percentage of embryos that ( P = 0.092) to increase fertilization rate. PROP reduced ( P = 0.028) fertilization rate, while LH tended
In addition, PROP tended ( P = 0.056) to decrease total number of Hormone-induced LH surge, although percentage of these follicles that ovulated wasĭecreased by both PROP ( P = 0.002) and LH ( P = 0.048). PROP increased glucose ( P 9 mm at time of gonadotropin-releasing
LH(HLH)-water plus HLH preparation (3) PROP-drenching with PROP plus low LH (4) Treatment groups were asįollows: (1) control-oral drenching with water plus low-LH preparation (2) high Increasing LH (3-fold) during last 2 days of superovulation. Hyperinsulinemia and associated metabolic changes. PROP was orally drenched every 4 h for 7 days to induce Hormone (LH) during antral follicle development on ovarian function, fertilization, andĮarly embryo quality. Seventeen nonlactating Holstein cows were superovulated in a Latin-square designedĮxperiment to determine the effects of increased propylene glycol (PROP) and luteinizing