Ovarian superstimulatory response and embryo production in mares treated with equine pituitary extract twice daily

Equine pituitary extract (EPE), has been reported to induce multiple ovulation in mares, however ovulation rates are poor in comparison to those obtained in other species. Attempts to improve the effectiveness of EPE for induction of superovulation in cyclic mares has focused on daily frequency of EPE treatment. Two experiments were performed to compare the ovarian response of cyclic mares given EPE once or twice-daily. Mares were assigned to one of two treatment groups 6 to 8 days after ovulation: prostaglandin was given once and EPE (25 mg) was given once daily (Group 1) or twice daily (Group 2). In Experiment 1, more (P < 0.05) follicles 35 mm were detected in mares treated with EPE twice daily (6.1 +/- 3.1) than in mares treated once a daily (2.0 +/- 0.6). In a second experiment, the embryo recovery rates of mares given the two EPE protocols used in Experiment 1 were compared. The number of ovulations per mare was higher (P < 0.05) for mares treated twice-daily (7.1 +/- 5.1, range 3 to 18) than for mares treated once daily (2.4 +/- 1.8, range 1 to 6). The number of embryos produced per mare was higher (P < 0.05) in mares in Group 2 (3.5) than in Group 1 (1.6).Although it is not clear whether the increased ovulation rate is due specifically to dose or frequency, twice-daily administration of a high dose of EPE significantly improved follicular development, ovulation and embryo recovery over the standard treatment of once-daily injection. (C) 2001 by Elsevier B.V.

Tests for ovarian reserve: reliability and utility

Purpose of review This review discusses ovarian reserve tests for ovulation induction and their application in determining fertility capacity, and their current applications to assess risk of natural ovarian failure and to estimate ovarian function after cancer treatment. Recent findings The current arsenal of ovarian reserve tests comprises hormonal markers [basal follicle stimulating hormone, estradiol, inhibin-B, antimullerian hormone (AMH)] and ultrasonographic markers [ovarian volume, antral follicle counts (AFCs)]. These markers have limitations in terms of which test(s) should be used to reliably predict ovarian reserve with regard to accuracy, invasiveness, cost, convenience, and utility. Several studies have correlated sonographic AFCs with serum AMH levels for predicting the ovarian response to ovulation induction protocols during assisted reproduction treatments. Summary Serum AMH levels and AFC are reliable tests for predicting the ovarian response to ovulation induction. However, none of the currently employed tests of ovarian reserve can reliably predict pregnancy after assisted conception. Further, ovarian reserve tests cannot predict the onset of reproductive and hormonal menopause; thus, they should be used with caution for reproductive life-programming counseling. Moreover, there is no evidence to support the use of ovarian reserve tests to estimate the risk of ovarian sufficiency after cancer treatments.

Anti-mullerian hormone is the best predictor of poor response in ICSI cycles of patients with endometriosis

Purpose: To correlate ovarian reserve (OR) markers with response in assisted reproduction techniques (ART) and determine their ability to predict poor response among patients with endometriosis (EDT). Methods: We evaluated ART cycles of 27 women with EDT and 50 with exclusive male factor. Basal follicle stimulating hormone (FSH) and anti-mullerian hormone (AMH) levels were determined. Ovarian response to gonadotropin stimulation was assessed and correlation coefficients calculated between the variables and reserve markers. Areas under the curve (AUC) determined ability of tests to predict poor response. Results: AMH was significantly correlated with response in both groups and it was the only marker with significant discriminative capacity to predict poor response among EDT (AUC = 0.842; 95% CI: 0.651-0.952) and control group (AUC = 0.869; 95% CI: 0.743-0.947). Conclusion: Infertile patients with endometriosis can benefit from the pre-therapeutic assessment of OR markers. However, regardless of disease presence, only AMH predicts poor response to stimulus.

The effect of exogenous gonadotropins on ovarian function in goats actively immunized against inhibin

The aim of this investigation was to compare the ovarian response to superovulatory treatments in does before and after inhibin immunization, with a view to optimizing the superovulatory potential of the caprine ovary. To avoid interference by the ovarian cycle, the experiment was conducted out-of-season. At the onset of the experiment 48 does were subjected to treatment with an sc implant of the progestogen norgestomet, combined with a gonadotropin; eight does each received a single injection of 1200 IU eCG, 400 IU eCG or 2 mL physiological saline (control) or six injections (at 12 h intervals) constituting 16 or 5.4 AU pFSH. The does were mated and subjected to embryo collection 6 to 7 d later. Throughout the experiment ovarian function (by ultrasonography) and plasma levels of inhibin antibodies and progesterone were monitored. Of 40 does treated during the first part of the experiment, 48% showed estrus. The ovarian response in does treated with a high or low dose of eCG or a low dose of pFSH was barely in excess of the ovarian response in the saline-treated controls, whereas a superovulatory dose of pFSH (16 AU) gave a satisfactory response of, on average, 14.5 ovulations (yielding 8.8 flushed ova and embryos). Immediately after the does had been subjected to embryo collection they were actively immunized against inhibin by administering two injections of a recombinant α-subunit of ovine inhibin at four week intervals. All immunized does produced antibodies with the maximal titer reached two weeks after the second injection. Groups of immunized does were subjected to the same gonadotropin treatments as before (avoiding allocation of individuals to the same treatments). This time all does showed estrous symptoms. The ovulatory response to the various treatments, including the saline controls, was virtually identical, the overall average being 21.8 follicles and 9.1 ovulations. The average embryo yield per doe was 5.7. The results imply that inhibin acted as the key factor in determining the ovulatory response since no impact of any of the supplementary gonadotropins was noted in inhibin-immunized does. This finding gives rise to the notion that inhibin antibodies may act primarily by an intraovarian paracrine action rather than by reducing the suppressive action of inhibin on pituitary FSH release. Further, these findings confirm earlier reports that eCG is less suitable than FSH for inducing superovulation in goats, and indicate that active immunization against inhibin may be considered a viable alternative to using exogenous gonadotropin for inducing superovulation in goats.

Decreased fertility in poor responder women is not related to oocyte morphological status

Introduction: In women showing impaired fertility, a decreased response to ovarian stimulation is a major problem, limiting the number of oocytes to be used for assisted reproduction techniques (ART). Despite the several definitions of poor response, it is still a matter of debate whether young poor responder patients also show a decrease in oocyte quality. The objective in this study was to investigate whether poor ovarian response to the superstimulation protocol is accompanied by impaired oocyte quality. Material and methods: This study included 313 patients younger than 35 years old, undergoing intracytoplasmic sperm injection. Patients with four or fewer MII oocytes (poor-responder group, PR, n = 57) were age-matched with normoresponder patients (NR, n = 256). Results: A higher rate of oocyte retrieval and a trend towards an increase in MII oocyte rate were observed in the NR group when compared to the PR group (71.6 +/- 1.1% and 74.1 +/- 1.0% vs. 56.3 +/- 2.9% and 66.5 +/- 3.7%; p < 0.0001 and p = 0.056, respectively). A trend toward increased implantation rates was observed in the NR group when compared to the PR group (44 and 24.5 +/- 2.0% vs. 28.8 and 16.4 +/- 3.9%; p = 0.0305 and p = 0.0651, respectively). Conclusions: Low response to ovarian stimulation is apparently not related to impaired oocyte quality. However, embryos produced from poor responder oocytes show impaired capacity to implant and to carry a pregnancy to term.

Bernard Michael Bindon - reproductive physiologist, animal scientist, research leader

This paper is a foreword to a series of papers commissioned on 'the impact of science on the beef industry', where the Beef CRC-related collaborative scientific work of Professor Bernard Michael Bindon will be reviewed. These papers will be presented in March 2006, as part of a 'festschrift' to recognise his wider contributions to the Australian livestock industries for over 40 years. Bindon's career involved basic and applied research in many areas of reproductive physiology, genetics, immunology, nutrition, meat science and more recently genomics, in both sheep and cattle. Together with his collaborators, he made large contributions to animal science by improving the knowledge of mechanisms regulating reproductive functions and in elucidating the physiology and genetics of high fecundity livestock. His collaborative studies with many colleagues of the reproductive biology and genetics of the Booroola Merino were amongst the most extensive ever conducted on domestic livestock. He was instrumental in the development of immunological techniques to control ovulation rate and in examining the application of these and other techniques to increase beef cattle reproductive output. This paper tracks his investigations and achievements both within Australia and internationally. In the later stages of his career he was the major influence in attracting a large investment in Cooperative Research Centres for the Australian cattle industry, in which he directed a multi-disciplinary approach to investigate, develop and disseminate science and technology to improve commercial cattle productivity.

Effects of melatonin on the endometrial morphology and embryo implantation in rats

Objective: To determine the effects of melatonin on rat endometrium morphology and embryo implantation. Design: Experimental study. Setting: Federal University of Sao Paulo, Brazil. Animal(s): Forty female rats. Intervention(s): GI: control, GII: sham-operated, GIII: pinealectomized, and GIV: pinealectomized rats that received melatonin during 3 months. The GI, GII, and Gin groups received the vehicle of melatonin (NaCl + ethanol). At the end of the treatment, the animals were killed during the estrous phase; the uterus was removed for morphometric analysis. Urine was collected for 6-sulfatoxymelatonin. Blood was collected for estrogen (E) and progesterone (P) level determinations. In a second experiment, female rats were used to evaluate the endometrial embryo implantation. Main Outcome Measure(s): Endometrial morphology and embryo implantation. Result(s): Gin presented the highest values for endometrial area and thickness index, number of endometrial glands, and eosinophils. The number of vessels of groups I, II, and IV was fewer than that of Gin. The highest number of eosinophils was detected in Gin in comparison to other groups. The implantation rate in Gin was the lowest of all groups. This implantation rate was significantly increased and restored toward normal in GIV. Conclusion(s): Our data suggested that, in nonphotoperiodic animals such as rats, melatonin may positively affect the endometrial morphology and improve embryo implantation.

In vitro fertilization, embryo development, and cell lineage segregation after pre- and/or postnatal exposure of female mice to ambient fine particulate matter

Objective: To evaluate effects of pre- and/or postnatal exposure to ambient fine particulate matter on fertilization, embryo development, and cell lineage segregation in preimplantation blastocysts using the IVF mouse model. Design: Animal model. Setting: Academic institution. Animal(S): Six-week-old, superovulated mice. Intervention(s): Pre- and postnatal exposure to filtered air (FA-FA), filtered-ambient air (FA-AA), or ambient air (AA-AA) in exposure chambers 24 hours a day for 9 weeks. Main Outcome Measure(S): Gestation length, litter size, sex ratio, ovarian response to superovulation, fertilization rate, embryo development, blastocyst and hatching rates, total cell count, and proportion of cell allocation to inner-cell mass (ICM) and trophectoderm (TE). Result(S): Gestation length, litter size and birth weight, live-birth index, and sex ratio were similar among exposure groups. Ovarian response was not affected by the exposure protocol. A multivariate effect for pre- and/or postnatal exposure to ambient fine particulate matter on IVF, embryo development, and blastocyst differential staining was found. Cell counts in ICM and ICM/TE ratios in blastocysts produced in the FA-FA protocol were significantly higher than in blastocysts produced in the FA-AA and AA-AA protocols. No difference in total cell count was observed among groups. Conclusion(S): Our study suggests that exposure to ambient fine particulate matter may negatively affect female reproductive health by disrupting the lineage specification at the blastocyst stage without interfering in early development of the mouse embryo. (Fertil Steril (R) 2009;92:1725-35. (C) 2009 by American Society for Reproductive Medicine.)

Increased basal FSH levels as predictors of low-quality follicles in infertile women with endometriosis

Objective: To determine whether basal levels of follicle-stimulating hormone (FSH) and anti-mullerian hormone (AMH), antral follicle count (AFC), and the numbers of dominant follicles, oocytes, and mature oocytes retrieved after ovarian stimulation differed between infertile women with endometriosis and healthy women undergoing assisted reproduction techniques (ART). Method: Of 77 consecutive ART candidates, 27 were infertile and had endometriosis. A male factor caused the infertility of the other 50, who acted as controls. Results: The AMH and AFC levels were similar in the 2 groups. The FSH levels were higher (8.28 mIU/ML [range, 5.25-24.1 mIU/ML] vs 5.91 mIU/mL [range, 2.47-18.7 mIU/ML]; P<0.01) in the study group. And the numbers of retrieved (n = 5 [range, 0-12] vs n = 9 [range, 0-27]; P<0.05) and mature oocytes (n = 4 [range, 0-11] vs n = 5 [range, 0-16]; P<0.05) were less in the study group. Conclusion: Because AMH levels were unchanged, endometriosis seems not to damage the primordial pool of follicles and oocytes, but to lessen the quality of the ovarian response to the hCG injection. Basal FSH levels may be of value in predicting ART success in women with the disease. (C) 2010 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Locus coeruleus mediates cold stress-induced polycystic ovary in rats

Previous reports about the rat ovary have shown that cold stress promotes ovarian morphological alterations related to a polycystic ovary (PCO) condition through activation of the ovarian sympathetic nerves. Because the noradrenergic nucleus locus coeruleus (LC) is activated by cold stress and synaptically connected to the preganglionic cell bodies of the ovarian sympathetic pathway, this study aimed to evaluate the LC`s role in cold stress-induced PCO in rats. Ovarian morphology and endocrine and sympathetic functions were evaluated after 8 wk of chronic intermittent cold stress (4 C, 3 h/d) in rats with or without LC lesion. The effect of acute and chronic cold stress upon the LC neuron activity was confirmed by Fos protein expression in tyrosine hydroxylase-immunoreactive neurons. Cold stress induced the formation of follicular cysts, type III follicles, and follicles with hyperthecosis alongside increased plasma estradiol and testosterone levels, irregular estrous cyclicity, and reduced ovulation. Considering estradiol release in vitro, cold stress potentiated the ovarian response to human chorionic gonadotropin. Ovarian norepinephrine (NE) was not altered after 8 wk of stress. However, LC lesion reduced NE activity in the ovary of cold-stressed rats, but not in controls, and prevented all the cold stress effects evaluated. Cold stress increased the number of Fos/tyrosine hydroxylase-immunoreactive neurons in the LC, but this effect was more pronounced for acute stress as compared with chronic stress. These results show that cold stress promotes PCO in rats, which apparently depends on ovarian NE activity that, under this condition, is regulated by the noradrenergic nucleus LC.

Lights and Shadows about the Effectiveness of IVF in HIV Infected Women: A Systematic Review

Background. HIV infected women have higher rates of infertility. Objective. The purpose of this literature review is to evaluate the effectiveness of fresh IVF/ICSI cycles in HIV infected women. Materials and Methods. A search of the PubMed database was performed to identify studies assessing fresh nondonor oocyte IVF/ICSI cycle outcomes of serodiscordant couples with an HIV infected female partner. Results and Discussion. Ten studies met the inclusion criteria. Whenever a comparison with a control group was available, with the exception of one case, ovarian stimulation cancelation rate was higher and pregnancy rate (PR) was lower in HIV infected women. However, statistically significant differences in both rates were only seen in one and two studies, respectively. A number of noncontrolled sources of bias for IVF outcome were identified. This fact, added to the small size of samples studied and heterogeneity in study design and methodology, still hampers the performance of a meta-analysis on the issue. Conclusion. Prospective matched case-control studies are necessary for the understanding of the specific effects of HIV infection on ovarian response and ART outcome.

Decreased fertility in poor responder women is not related to oocyte morphological status

Introduction: In women showing impaired fertility, a decreased response to ovarian stimulation is a major problem, limiting the number of oocytes to be used for assisted reproduction techniques (ART). Despite the several definitions of poor response, it is still a matter of debate whether young poor responder patients also show a decrease in oocyte quality. The objective in this study was to investigate whether poor ovarian response to the superstimulation protocol is accompanied by impaired oocyte quality.Material and methods: This study included 313 patients younger than 35 years old, undergoing intracytoplasmic sperm injection. Patients with four or fewer MII oocytes (poor-responder group, PR, n = 57) were age-matched with normoresponder patients (NR, n = 256).Results: A higher rate of oocyte retrieval and a trend towards an increase in MII oocyte rate were observed in the NR group when compared to the PR group (71.6 +/- 1.1% and 74.1 +/- 1.0% vs. 56.3 +/- 2.9% and 66.5 +/- 3.7%; p < 0.0001 and p = 0.056, respectively). A trend toward increased implantation rates was observed in the NR group when compared to the PR group (44 and 24.5 +/- 2.0% vs. 28.8 and 16.4 +/- 3.9%; p = 0.0305 and p = 0.0651, respectively).Conclusions: Low response to ovarian stimulation is apparently not related to impaired oocyte quality. However, embryos produced from poor responder oocytes show impaired capacity to implant and to carry a pregnancy to term.

Are poor responders patients at higher risk for producing aneuploid embryos in vitro?

Purpose To test the hypothesis that aged women with poor ovarian response express an increase on embryo chromosomal alterations when compared to aged women who presented normal response.Methods Couples undergoing intracytoplasmic sperm injection cycles with preimplantation genetic screening, were subdivided into two groups: Poor Responder group (n = 34), patients who produced a parts per thousand currency sign4 oocytes; and Normoresponder group (n = 50), patients who produced a parts per thousand yen5 oocytes. Groups were compared regarding cycles' outcomes and aneuploidy frequency.Results There were no significant differences between and groups regarding the fertilization rate (p = 0.6861), clinical pregnancy (p = 0.9208), implantation (p = 0.6863), miscarriage (p = 0.6788) and the percentage of aneuploid embryos (p = 0.270). Embryo transfer rate was significantly lower on poor responder group (p = 0.0128) and logistic regression confirmed the influence of poor response on the chance of embryo transfer (p = 0.016).Conclusions Aged females responding poorly to gonadotrophins are not at a higher risk for producing aneuploid embryos in vitro.

Superovulation in mares: Limitations and perspectives

Superovulation is an important tool for routine use in equine embryo transfer (ET) in order to reduce the costs and to enhance the efficiency of ET programs. Satisfactory superovulatory answers (2-7 ovulations) have been reported in mares treated with Equine Pituitary Extract (EPE) and more recently using a commercial Equine FSH. However, embryo recovery rates have been inconsistent and below expectations (20-50% embryos/ovulation). Recent studies have shown that superovulatory treatment leads to disturbances in oocyte maturation and transport, especially in mares with a high ovarian response. Higher and more consistent embryo recovery rates per ovulation have been observed in mares treated with lower doses of EPE. This paper presents a review of recent studies related to superovulation in mares.

Effects of two estradiol esters (benzoate and cypionate) on the induction of synchronized ovulations in Bos indicus cows submitted to a timed artificial insemination protocol

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