Dr. Yaakov Bentov graduated doctoral studies in medicine from Ben-Gurion University, in Israel in 1994 with Honors (Valedictorian), after which he pursued a Master’s degree in Medical Business Administration (MBA), also at Ben-Gurion University, from 1995 to 2000. During his years as a medical school student, he started a bachelor’s degree program in emergency medicine for paramedics and was the Program Head during 1996-2004. Dr. Bentov completed his internship and residency in obstetrics/gynecology at Ben-Gurion University from 1995 to 2002. He later went on to do a fellowship in Reproductive Endocrinology and Infertility under the direction of Dr. Robert Casper at the University of Toronto. Dr Bentov has been an assistant professor in the OB/GYN department of the University of Toronto since 2009-2017 and currently affiliated with McMaster university. Phone: +972-50-517-2140 Address: 25 Avondale Ave Unit 313, Toronto, ON Canada M2N 7C1
Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology, Jan 18, 2018
Many Patients with persistent retained products of conception prefers to avoid surgical intervent... more Many Patients with persistent retained products of conception prefers to avoid surgical interventions, such as a dilatation and curettage (D&C) that might pose an additional future risk to their already compromised fertility or obstetric performance. The aim of this study was to the possibility of induced withdrawal bleeding following oral contraceptive administration as a non-surgical treatment for patients with persistent retained products of conception (RPOC). A retrospective study of patients presenting with retained products of conception (RPOC) after failed expectant management or after treatment with PGE1 was performed. Twelve women presenting with RPOC at ≤8 weeks gestation with minimal to mild vaginal bleeding and no signs of infection were treated with oral contraceptive pill (OCP) containing 0.03 mg ethinylestradiol and 0.15 mg of desogestrel for 3 weeks. Out of the 12 patients treated, nine women (75%) successfully expelled the RPOC after completing the three-week course...
Metformin, a drug developed for the treatment of patients with type II diabetes, has become commo... more Metformin, a drug developed for the treatment of patients with type II diabetes, has become commonly prescribed medication for PCOS patients. Initially, metformin was prescribed for patients with impaired glucose tolerance at the pre conception period, however more recently its use was expanded to many of the PCOS patients and for the whole duration of pregnancy. Several studies examining the effects of Metformin during pregnancy reported a lower pregnancy loss, reduced gestational diabetes and no increased risk for birth defects, however, several more recent studies also raised concerns about its safe use. The therapeutic effect of metformin stems from its ability to inhibit the action of the first complex of the electron transport resulting in reduced ATP production. At the initial stages of embryo development, the only source of ATP is the mitochondrial electron transport chain. Lowering ATP production at the critical stage of early embryo development may impair oocyte maturation...
Journal of assisted reproduction and genetics, Jan 6, 2016
The aim of this study was to compare the pregnancy rates between good quality blastocysts vitrifi... more The aim of this study was to compare the pregnancy rates between good quality blastocysts vitrified on day 6 versus blastocysts vitrified on day 5 after fertilization. This is a retrospective cohort study of 791 freeze-thaw cycles of blastocysts vitrified either on day 5 or on day 6 and transferred between January 2012 and October 2015. Five hundred and thirty-seven cycles included blastocysts vitrified on day 5, and 254 cycles included blastocysts vitrified on day 6. The age of the patients and the proportion of embryos that survived the thawing process were comparable between the two groups. More good quality embryos were transferred in the group in which blastocysts were vitrified on day 6 (1.2 vs. 1.3, p = 0.005), but the clinical pregnancy rate (44 vs. 33 %, p = 0.002) and the ongoing pregnancy rate (41 vs. 28 %, p < 0.001) were higher in the group in which blastocysts were vitrified on day 5. Multivariate regression analysis adjusting for patient's age, number of good q...
Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenit... more Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenital malformations are caused by three factors: genetic, environmental or multifactorial, all of which are present in the context of artificial reproductive techniques. In 1999 Bergh et al. conducted a retrospective study, which included all the children born following IVF treatment in Sweden. The relative risk found was RR = 1.39 [95% CI 1.25-1.54] and there was no stratification for maternal age and parity. In 2002 Hansen et al. conducted a well-established retrospective study in Western Australia. When only term singletons were included in the study, the OR found was OR = 2.1 [1.4-3.2] in the IVF group and OR = 2.2 [1.2-4] in the ICSI group. Results were stratified for maternal age, parity and offspring sex. A meta-analysis of 19 studies found a relative risk of 1.29 for major malformations among IVF pregnancies. Explanations for the increased risk of fetal malformations could be divided into three categories: first, the characteristics of the infertile population which include many risk factors: older age, lower parity, chronic diseases and infertility itself. Second, the techniques used to treat infertility are not physiologic. Third, the characteristics of the pregnancy achieved: the incidence of high-order pregnancies is much greater and this fact exposes the offspring to other risk factors such as preterm birth and low birth weight. Major advances in reproductive techniques offered hope for many couples, but they were also the reason for much concern regarding the outcome of the awaited offspring. The recent studies seem to justify some of those doubts.
Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenit... more Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenital malformations are caused by three factors: genetic, environmental or multifactorial, all of which are present in the context of artificial reproductive techniques. In 1999 Bergh et al. conducted a retrospective study, which included all the children born following IVF treatment in Sweden. The relative risk found was RR = 1.39 [95% CI 1.25-1.54] and there was no stratification for maternal age and parity. In 2002 Hansen et al. conducted a well-established retrospective study in Western Australia. When only term singletons were included in the study, the OR found was OR = 2.1 [1.4-3.2] in the IVF group and OR = 2.2 [1.2-4] in the ICSI group. Results were stratified for maternal age, parity and offspring sex. A meta-analysis of 19 studies found a relative risk of 1.29 for major malformations among IVF pregnancies. Explanations for the increased risk of fetal malformations could be divide...
Clinical medicine insights. Reproductive health, 2014
The age-related reduction in live-birth rate is attributed to a high rate of aneuploidy and folli... more The age-related reduction in live-birth rate is attributed to a high rate of aneuploidy and follicle depletion. We showed in an animal model that treatment with Coenzyme Q10 (CoQ10) markedly improved reproductive outcome. The aim of this study was to compare the post-meiotic oocyte aneuploidy rate in in vitro fertilization (IVF) and intra cytoplasmic sperm injection (ICSI) patients treated with CoQ10 or placebo. We conducted a double blind placebo controlled randomized trial that included IVF-ICSI patients 35-43 years of age. The patients were treated with either 600 mg of CoQ10 or an equivalent number of placebo caps. We compared the post-meiotic aneuploidy rate using polar body biopsy (PBBX) and comparative genomic hybridization (CGH). According to the power calculation, 27 patients were needed for each arm. Owing to safety concerns regarding the effects of polar body biopsy on embryo quality and implantation, the study was terminated before reaching the target number of participa...
Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology, Jan 18, 2018
Many Patients with persistent retained products of conception prefers to avoid surgical intervent... more Many Patients with persistent retained products of conception prefers to avoid surgical interventions, such as a dilatation and curettage (D&C) that might pose an additional future risk to their already compromised fertility or obstetric performance. The aim of this study was to the possibility of induced withdrawal bleeding following oral contraceptive administration as a non-surgical treatment for patients with persistent retained products of conception (RPOC). A retrospective study of patients presenting with retained products of conception (RPOC) after failed expectant management or after treatment with PGE1 was performed. Twelve women presenting with RPOC at ≤8 weeks gestation with minimal to mild vaginal bleeding and no signs of infection were treated with oral contraceptive pill (OCP) containing 0.03 mg ethinylestradiol and 0.15 mg of desogestrel for 3 weeks. Out of the 12 patients treated, nine women (75%) successfully expelled the RPOC after completing the three-week course...
Metformin, a drug developed for the treatment of patients with type II diabetes, has become commo... more Metformin, a drug developed for the treatment of patients with type II diabetes, has become commonly prescribed medication for PCOS patients. Initially, metformin was prescribed for patients with impaired glucose tolerance at the pre conception period, however more recently its use was expanded to many of the PCOS patients and for the whole duration of pregnancy. Several studies examining the effects of Metformin during pregnancy reported a lower pregnancy loss, reduced gestational diabetes and no increased risk for birth defects, however, several more recent studies also raised concerns about its safe use. The therapeutic effect of metformin stems from its ability to inhibit the action of the first complex of the electron transport resulting in reduced ATP production. At the initial stages of embryo development, the only source of ATP is the mitochondrial electron transport chain. Lowering ATP production at the critical stage of early embryo development may impair oocyte maturation...
Journal of assisted reproduction and genetics, Jan 6, 2016
The aim of this study was to compare the pregnancy rates between good quality blastocysts vitrifi... more The aim of this study was to compare the pregnancy rates between good quality blastocysts vitrified on day 6 versus blastocysts vitrified on day 5 after fertilization. This is a retrospective cohort study of 791 freeze-thaw cycles of blastocysts vitrified either on day 5 or on day 6 and transferred between January 2012 and October 2015. Five hundred and thirty-seven cycles included blastocysts vitrified on day 5, and 254 cycles included blastocysts vitrified on day 6. The age of the patients and the proportion of embryos that survived the thawing process were comparable between the two groups. More good quality embryos were transferred in the group in which blastocysts were vitrified on day 6 (1.2 vs. 1.3, p = 0.005), but the clinical pregnancy rate (44 vs. 33 %, p = 0.002) and the ongoing pregnancy rate (41 vs. 28 %, p < 0.001) were higher in the group in which blastocysts were vitrified on day 5. Multivariate regression analysis adjusting for patient's age, number of good q...
Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenit... more Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenital malformations are caused by three factors: genetic, environmental or multifactorial, all of which are present in the context of artificial reproductive techniques. In 1999 Bergh et al. conducted a retrospective study, which included all the children born following IVF treatment in Sweden. The relative risk found was RR = 1.39 [95% CI 1.25-1.54] and there was no stratification for maternal age and parity. In 2002 Hansen et al. conducted a well-established retrospective study in Western Australia. When only term singletons were included in the study, the OR found was OR = 2.1 [1.4-3.2] in the IVF group and OR = 2.2 [1.2-4] in the ICSI group. Results were stratified for maternal age, parity and offspring sex. A meta-analysis of 19 studies found a relative risk of 1.29 for major malformations among IVF pregnancies. Explanations for the increased risk of fetal malformations could be divided into three categories: first, the characteristics of the infertile population which include many risk factors: older age, lower parity, chronic diseases and infertility itself. Second, the techniques used to treat infertility are not physiologic. Third, the characteristics of the pregnancy achieved: the incidence of high-order pregnancies is much greater and this fact exposes the offspring to other risk factors such as preterm birth and low birth weight. Major advances in reproductive techniques offered hope for many couples, but they were also the reason for much concern regarding the outcome of the awaited offspring. The recent studies seem to justify some of those doubts.
Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenit... more Major congenital malformations are a leading cause of perinatal morbidity and mortality. Congenital malformations are caused by three factors: genetic, environmental or multifactorial, all of which are present in the context of artificial reproductive techniques. In 1999 Bergh et al. conducted a retrospective study, which included all the children born following IVF treatment in Sweden. The relative risk found was RR = 1.39 [95% CI 1.25-1.54] and there was no stratification for maternal age and parity. In 2002 Hansen et al. conducted a well-established retrospective study in Western Australia. When only term singletons were included in the study, the OR found was OR = 2.1 [1.4-3.2] in the IVF group and OR = 2.2 [1.2-4] in the ICSI group. Results were stratified for maternal age, parity and offspring sex. A meta-analysis of 19 studies found a relative risk of 1.29 for major malformations among IVF pregnancies. Explanations for the increased risk of fetal malformations could be divide...
Clinical medicine insights. Reproductive health, 2014
The age-related reduction in live-birth rate is attributed to a high rate of aneuploidy and folli... more The age-related reduction in live-birth rate is attributed to a high rate of aneuploidy and follicle depletion. We showed in an animal model that treatment with Coenzyme Q10 (CoQ10) markedly improved reproductive outcome. The aim of this study was to compare the post-meiotic oocyte aneuploidy rate in in vitro fertilization (IVF) and intra cytoplasmic sperm injection (ICSI) patients treated with CoQ10 or placebo. We conducted a double blind placebo controlled randomized trial that included IVF-ICSI patients 35-43 years of age. The patients were treated with either 600 mg of CoQ10 or an equivalent number of placebo caps. We compared the post-meiotic aneuploidy rate using polar body biopsy (PBBX) and comparative genomic hybridization (CGH). According to the power calculation, 27 patients were needed for each arm. Owing to safety concerns regarding the effects of polar body biopsy on embryo quality and implantation, the study was terminated before reaching the target number of participa...
8 The need to find an efficient method to store gametes and embryos was driven both by 9 medical ... more 8 The need to find an efficient method to store gametes and embryos was driven both by 9 medical and agricultural necessities. Gametes were the first cells used in early attempts 10 of cryopreservation, yet these proved to be the most elusive. This chapter details the 11 story of the development of techniques for gamete and embryo freezing, starting with 12 hot air balloons and ending with cryotop open vitrification systems. Since gametes were 13 the first cells to be frozen and the last to successfully thaw, their story provides an 14 overview of the development of the science of cryopreservation.
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