Toronto Center for Advanced Reproductive Technology

Toronto, Canada

Toronto Center for Advanced Reproductive Technology

Toronto, Canada
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Javed M.,Toronto Center for Advanced Reproductive Technology | Esfandiari N.,Toronto Center for Advanced Reproductive Technology | Esfandiari N.,University of Toronto | Casper R.F.,Toronto Center for Advanced Reproductive Technology | Casper R.F.,University of Toronto
Reproductive BioMedicine Online | Year: 2010

Intracytoplasmic sperm injection (ICSI) has resulted in pregnancy and birth for many couples, including those with severe male factor infertility. However, even after ICSI, complete failure of fertilization occurs in 1-3% of cycles. Most cases occur due to low number of mature oocytes, failure of oocyte activation or non-availability of appropriate spermatozoa for injection. Given the significant emotional and financial involvement in assisted reproductive cycles, failure of fertilization in all mature oocytes is a distressful event. It is not predictable. Since follow-up ICSI cycles result in fertilization in 85% of cases, repeated ICSI attempts are suggested. Physicians should counsel patients experiencing repeated failure of fertilization after ICSI cycles about available options including donated oocytes/embryos, donor sperm insemination, adoption or remaining childless if these choices are not acceptable due to religious or ethical reasons. This review discusses the causes and remedies for failed fertilization after clinical ICSI. © 2009, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.


Gomaa H.,Toronto Center for Advanced Reproductive Technology | Gomaa H.,University of Toronto | Gomaa H.,Samuel Lunenfeld Research Institute | Casper R.F.,Toronto Center for Advanced Reproductive Technology | And 9 more authors.
Reproductive Biology and Endocrinology | Year: 2012

Background: To compare the outcome of IVF cycles in women receiving controlled ovarian stimulation with recFSH or recFSH plus low dose hCG.Methods: A retrospective case control study, performed at a private practice affiliated with an academic institute. Patients were infertile women who were treated with IVF/ICSI and controlled ovarian stimulation in a long GnRH agonist protocol using either low dose hCG in addition to recFSH [N = 88] or recFSH alone [N = 99]. Primary outcomes were mean FSH dose, number of mature eggs, number of fertilized eggs, and serum levels of estradiol. Secondary outcomes were endometrial thickness, cycle cancellations and pregnancy rates.Results: A significant increase in number of mature and fertilized eggs was observed in women over 40 years of age using low dose hCG in addition to recFSH. The estradiol level was significantly higher on the day of hCG administration and the serum level of FSH on cycle day 7 and on the day of hCG administration were lower.Conclusion: Addition of low dose hCG to recFSH compared with recFSH alone significantly modified cycle characteristics in patients >/= 40 years and could be of potential benefit for IVF cycles in older infertile women. © 2012 Gomaa et al.; licensee BioMed Central Ltd.


Bentov Y.,Toronto Center for Advanced Reproductive Technology | Bentov Y.,University of Toronto | Bentov Y.,Samuel Lunenfeld Research Institute | Esfandiari N.,Toronto Center for Advanced Reproductive Technology | And 11 more authors.
Fertility and Sterility | Year: 2010

Objective: To report an ongoing pregnancy after in vitro fertilization (IVF) with ovarian stimulation using a gonadotropin-releasing hormone (GnRH) antagonist that resulted in two waves of follicular growth. Design: Case report. Setting: University of Toronto affiliated infertility clinic. Patient(s): A 33-year-old woman with a 3-year history of secondary infertility. Intervention(s): In vitro fertilization and embryo transfer. Main Outcome Measure(s): Ongoing pregnancy. Result(s): This patient successfully conceived after the GnRH antagonist-induced demise of the first cohort of follicles and the emergence of a second wave of follicles followed by oocyte retrieval on cycle day 30 and fresh embryo transfer. Conclusion(s): This case report is consistent with previous observations of multiple waves of follicle recruitment and growth per cycle. The window of implantation may not be adversely affected by prolonged or even variable estrogen exposure in the follicular phase of the cycle. © 2010 American Society for Reproductive Medicine.


Casper R.F.,Samuel Lunenfeld Research Institute | Casper R.F.,Toronto Center for Advanced Reproductive Technology | Mitwally M.F.M.,Texas Tech University
Fertility and Sterility | Year: 2012

The concept of using aromatase inhibitors in place of clomiphene citrate (CC) for ovulation induction was introduced >10 years ago; a brief history of its development is presented. Its worldwide usage for ovulation induction, including as an adjunct for intrauterine insemination and in vitro fertilization has occurred despite the absence of definitive data of superiority to CC. The results of two ongoing potentially definitive multicenter trials of efficacy and safety of letrozole compared with CC are eagerly awaited. © 2012 by American Society for Reproductive Medicine.


Casper R.F.,University of Toronto | Casper R.F.,Samuel Lunenfeld Research Institute | Casper R.F.,Toronto Center for Advanced Reproductive Technology | Mitwally M.F.M.,University of Toronto
Clinical Obstetrics and Gynecology | Year: 2011

Clomiphene citrate (CC) is the most commonly used oral agent for the induction of ovulation. It is a nonsteroidal selective estrogen receptor modulator that has predominant antiestrogenic action resulting in long-lasting estrogen receptor depletion. Side effects include antiestrogenic effects systemically and on the endometrium and cervical mucous. Letrozole is a potent, nonsteroidal, aromatase inhibitor, originally used for postmenopausal breast cancer therapy, at present its only registered indication. We hypothesized that letrozole could mimic the action of CC without depletion of estrogen receptors. As there is no estrogen receptor antagonism, antiestrogenic effects such as poor cervical mucus and thin endometrium are not expected with aromatase inhibitor treatment. In addition, because estrogen receptors in the brain are not depleted, normal negative feedback occurs with letrozole and generally results in monoovulation. We and others have demonstrated the success of aromatase inhibition in inducing ovulation in women with polycystic ovarian syndrome. Letrozole may be very effective for ovulation induction and pregnancy in cases of CC resistance. When used together with follicle-stimulating hormone (FSH) injections, letrozole resulted in a significant reduction in the FSH dose needed for controlled ovarian hyperstimulation. Aromatase inhibitors likely increase ovarian sensitivity to FSH, and may be useful in poor responders and in women undergoing ovarian stimulation for in vitro fertilization. The safety of letrozole in pregnancy outcome studies has been demonstrated by examination of spontaneous pregnancy loss, multiple pregnancy rates, and congenital anomalies compared with a control group of infertility patients treated with CC. In addition, new data suggest that CC may result in cardiac anomalies and other birth defects and in low birth weight babies. We believe aromatase inhibitors are acceptable alternatives to CC as first line oral agents for ovulation induction or controlled ovarian stimulation. © 2011 Lippincott Williams & Wilkins.


Leung C.,University of Toronto | Lu Z.,University of Toronto | Esfandiari N.,Toronto Center for Advanced Reproductive Technology | Casper R.F.,University of Toronto | Sun Y.,University of Toronto
IEEE Transactions on Biomedical Engineering | Year: 2011

Sperm immobilization is a requisite step in intracytoplasmic sperm injection (ICSI). Conventionally, sperm immobilization is performed manually, which entails long training hours and stringent skills. Manual sperm immobilization also has the limitation of low success rates and poor reproducibility due to human fatigue and skill variations across operators. This paper presents a system for fully automated sperm immobilization to eliminate limitations in manual operation. Integrating computer vision and motion control algorithms, the automated system is able to visually track a sperm and control a micropipette to immobilize the sperm. A robust sperm tail tracking algorithm is developed to locate the optimal position on the sperm tail for sperm immobilization. The system demonstrates: 1) an average sperm tail tracking error of 0.95 μ m; 2) a sperm tail visual tracking success rate of 96%; 3) a sperm immobilization success rate of 88.2% (based on 1000 trials); and 4) a speed of 6-7 s per successful immobilization. © 2011 IEEE.


PubMed | Toronto Center for Advanced Reproductive Technology
Type: Journal Article | Journal: Reproductive biomedicine online | Year: 2010

Intracytoplasmic sperm injection (ICSI) has resulted in pregnancy and birth for many couples, including those with severe male factor infertility. However, even after ICSI, complete failure of fertilization occurs in 1-3% of cycles. Most cases occur due to low number of mature oocytes, failure of oocyte activation or non-availability of appropriate spermatozoa for injection. Given the significant emotional and financial involvement in assisted reproductive cycles, failure of fertilization in all mature oocytes is a distressful event. It is not predictable. Since follow-up ICSI cycles result in fertilization in 85% of cases, repeated ICSI attempts are suggested. Physicians should counsel patients experiencing repeated failure of fertilization after ICSI cycles about available options including donated oocytes/embryos, donor sperm insemination, adoption or remaining childless if these choices are not acceptable due to religious or ethical reasons. This review discusses the causes and remedies for failed fertilization after clinical ICSI.


PubMed | Toronto Center for Advanced Reproductive Technology
Type: Journal Article | Journal: Journal of andrology | Year: 2012

The objective of this study was to determine the effects of low-level laser light exposure on the motility of spermatozoa and on DNA damage. Thirty-three semen samples were collected for routine analysis and were classified as normospermic, oligospermic, or asthenospermic. After routine semen analysis was performed, residual semen was divided into treated and control aliquots. Treated samples were exposed to a 30-second infrared laser pulse of 50 mW/cm(2) at 905 nm, a wavelength thought to increase light-sensitive cytochrome c oxidase in the mitochondrial electron transport chain. Samples were then incubated at 37C, and aliquots were analyzed at 30 minutes and 2 hours using computerassisted semen analysis. After incubation, 250 L of each sample was frozen at 280C until DNA fragmentation analysis by flow cytometry. A significant increase in motility, most prominent in oligospermic and asthenospermic samples (85% increase), was observed 30 minutes after the treatment (P < .0001). No significant increase in DNA damage compared with control samples was observed. Significant changes in sperm motion kinetics were observed. Low-level laser light exposure appears to have a positive short-term effect on the motility of treated spermatozoa and did not cause any increase in DNA damage measured at 2 hours. We conclude that some cases of asthenospermia may be related to mitochondrial dysfunction. The implications of this study in terms of future clinical applications needs further investigation.


PubMed | Toronto Center for Advanced Reproductive Technology
Type: Case Reports | Journal: Fertility and sterility | Year: 2010

To report an ongoing pregnancy after in vitro fertilization (IVF) with ovarian stimulation using a gonadotropin-releasing hormone (GnRH) antagonist that resulted in two waves of follicular growth.Case report.University of Toronto affiliated infertility clinic.A 33-year-old woman with a 3-year history of secondary infertility.In vitro fertilization and embryo transfer.Ongoing pregnancy.This patient successfully conceived after the GnRH antagonist-induced demise of the first cohort of follicles and the emergence of a second wave of follicles followed by oocyte retrieval on cycle day 30 and fresh embryo transfer.This case report is consistent with previous observations of multiple waves of follicle recruitment and growth per cycle. The window of implantation may not be adversely affected by prolonged or even variable estrogen exposure in the follicular phase of the cycle.


PubMed | Toronto Center for Advanced Reproductive Technology
Type: | Journal: Reproductive biology and endocrinology : RB&E | Year: 2013

When stimulating a patient with poor ovarian response for IVF, the maximal dose of gonadotropins injected is often determined by arbitrary standards rather than a measured response. The purpose of this study was to determine if serum FSH concentration during an IVF stimulation cycle reflects follicular utilization of FSH and whether serum FSH values may inform dose adjustments of exogenous FSH.In this retrospective cross sectional study we studied 155 consecutive IVF cycles stimulated only with recombinant human FSH. We only included long GnRH agonist protocols in which endogenous FSH levels were suppressed. We correlated the serum concentration of cycle day (CD) 7 FSH with the number of oocytes retrieved, cleaving embryos and pregnancy rate.We found that a CD7 FSH concentration above 22IU/L was associated with poor response regardless of the daily dose of FSH injected and a lower pregnancy rate.We concluded that CD7 FSH concentration during stimulation could be used to guide FSH dosing in poor responders. If the CD7 FSH concentration is above 22IU/L increasing the dose of FSH in an attempt to recruit more growing follicles is unlikely to be successful.

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