Jon Havelock
University of Texas Southwestern Medical Center
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Biology of Reproduction | 2005
Jon Havelock; Patrick W. Keller; Ndaya Muleba; Bobbie Mayhew; Brian M. Casey; William E. Rainey; R. Ann Word
Abstract Identification of temporal and spatial changes in myometrial gene expression during parturition may further the understanding of the coordinated regulation of myometrial contractions during parturition. The objective of this study was to compare the gene expression profiles of human fundal myometrium from pregnant women before and after the onset of labor using a functional genomics approach, and to further characterize the spatial and temporal expression patterns of three genes believed to be important in parturition. Fundal myometrial mRNA was isolated from five women in labor and five women not in labor, and analyzed using human UniGEM-V microarrays with 9182 cDNA elements. Real-time polymerase chain reaction using myometrial RNA from pregnant women in labor or not in labor was used to examine mRNA levels for three of the genes; namely, prostaglandin-endoperoxide synthase 2 (PTGS2), calgranulin B (S100A9), and oxytocin receptor (OXTR). The spatial expression pattern of these genes throughout the pregnant uterus before and after labor was also determined. Immunolocalization of cyclooxygenase-2 (also known as PTGS2) and S100A9 within the uterine cervix and myometrium were analyzed by immunohistochemistry. Few genes were differentially expressed in fundal myometrial tissues at term with the onset of labor. However, there appears to be a subset of genes important in the parturition cascade. The cellular properties of S100A9, its spatial localization, and dramatic increase in cervix and myometrium of women in labor suggest that this protein may be very important in the initiation or propagation of human labor.
Journal of obstetrics and gynaecology Canada | 2011
Kimberly E. Liu; Allison Case; Anthony P. Cheung; Sony Sierra; Saleh AlAsiri; Belina Carranza-Mamane; Cathie Dwyer; James Graham; Jon Havelock; Robert Hemmings; Francis Lee; Ward Murdock; Vyta Senikas; Tannys D.R. Vause; Benjamin Chee-Man Wong
OBJECTIVE To improve awareness of the natural age-related decline in female and male fertility with respect to natural fertility and assisted reproductive technologies (ART) and provide recommendations for their management, and to review investigations in the assessment of ovarian aging. OPTIONS This guideline reviews options for the assessment of ovarian reserve and fertility treatments using ART with women of advanced reproductive age presenting with infertility. OUTCOMES The outcomes measured are the predictive value of ovarian reserve testing and pregnancy rates with natural and assisted fertility. EVIDENCE Published literature was retrieved through searches of PubMed or Medline, CINAHL, and The Cochrane Library in June 2010, using appropriate key words (ovarian aging, ovarian reserve, advanced maternal age, advanced paternal age, ART). Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated into the guideline to December 2010. VALUES The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table). BENEFITS, HARMS, AND COSTS Primary and specialist health care providers and women will be better informed about ovarian aging and the age-related decline in natural fertility and about options for assisted reproductive technology. RECOMMENDATIONS 1. Women in their 20s and 30s should be counselled about the age-related risk of infertility when other reproductive health issues, such as sexual health or contraception, are addressed as part of their primary well-woman care. Reproductive-age women should be aware that natural fertility and assisted reproductive technology success (except with egg donation) is significantly lower for women in their late 30s and 40s. (II-2A) 2. Because of the decline in fertility and the increased time to conception that occurs after the age of 35, women > 35 years of age should be referred for infertility work-up after 6 months of trying to conceive. (III-B) 3. Ovarian reserve testing may be considered for women ≥ 35 years of age or for women < 35 years of age with risk factors for decreased ovarian reserve, such as a single ovary, previous ovarian surgery, poor response to follicle-stimulating hormone, previous exposure to chemotherapy or radiation, or unexplained infertility. (III-B) 4. Ovarian reserve testing prior to assisted reproductive technology treatment may be used for counselling but has a poor predictive value for non-pregnancy and should be used to exclude women from treatment only if levels are significantly abnormal. (II-2A) 5. Pregnancy rates for controlled ovarian hyperstimulation are low for women > 40 years of age. Women > 40 years should consider IVF if they do not conceive within 1 to 2 cycles of controlled ovarian hyperstimulation. (II-2B) 6. The only effective treatment for ovarian aging is oocyte donation. A woman with decreased ovarian reserve should be offered oocyte donation as an option, as pregnancy rates associated with this treatment are significantly higher than those associated with controlled ovarian hyperstimulation or in vitro fertilization with a womans own eggs. (II-2B) 7. Women should be informed that the risk of spontaneous pregnancy loss and chromosomal abnormalities increases with age. Women should be counselled about and offered appropriate prenatal screening once pregnancy is established. (II-2A) 8. Pre-conception counselling regarding the risks of pregnancy with advanced maternal age, promotion of optimal health and weight, and screening for concurrent medical conditions such as hypertension and diabetes should be considered for women > age 40. (III-B) 9. Advanced paternal age appears to be associated with an increased risk of spontaneous abortion and increased frequency of some autosomal dominant conditions, autism spectrum disorders, and schizophrenia. Men > age 40 and their partners should be counselled about these potential risks when they are seeking pregnancy, although the risks remain small. (II-2C).
Molecular and Cellular Endocrinology | 2004
Jon Havelock; William E. Rainey; Bruce R. Carr
The ovary is a complex endocrine gland responsible for production of sex steroids and is the source of fertilizable ova for reproduction. It also produces various growth factors, transcription factors and cytokines that assist in the complex signaling pathways of folliculogenesis. The ovary possesses two primary steroidogenic cell types. The theca cells (and to a lesser extent, the stroma) are responsible for androgen synthesis, and the granulosa cells are responsible for conversion of androgens to estrogens, as well as progesterone synthesis. These cells undergo a transformation in the luteal phase of the menstrual cycle, converting them from estrogen producing, to predominantly progesterone producing cells. Understanding the molecular mechanisms regulating these cells is essential in understanding the regulation of steroidogenesis and reproduction. Creation of appropriate in vitro cell model systems can provide important tools for the study of ovarian function. This has led to the development of ovarian steroidogenic cell lines in several laboratories. Developing theca cell lines has met with limited success. Conversely, numerous human and animal granulosa cell lines have been developed. This review will discuss the existing granulosa cell lines and their characteristics.
Journal of obstetrics and gynaecology Canada | 2015
Belina Carranza-Mamane; Jon Havelock; Robert Hemmings; Anthony P. Cheung; Sony Sierra; Allison Case; Dwyer Cathie; James Graham; Kimberly E. Liu; Ward Murdock; Tannys D.R. Vause; Benjamin Wong; Margaret Burnett
OBJECTIVE To provide recommendations regarding the best management of fibroids in couples who present with infertility. Usual and novel treatment options for fibroids will be reviewed with emphasis on their applicability in women who wish to conceive. OPTIONS Management of fibroids in women wishing to conceive first involves documentation of the presence of the fibroid and determination of likelihood of the fibroid impacting on the ability to conceive. Treatment of fibroids in this instance is primarily surgical, but must be weighed against the evidence of surgical management improving clinical outcomes, and risks specific to surgical management and approach. OUTCOMES The outcomes of primary concern are the improvement in pregnancy rates and outcomes with management of fibroids in women with infertility. EVIDENCE Published literature was retrieved through searches of PubMed, MEDLINE, the Cochrane Library in November 2013 using appropriate controlled vocabulary (e.g., leiomyoma, infertility, uterine artery embolization, fertilization in vitro) and key words (e.g., fibroid, myomectomy). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English and French. There were no date restrictions. Searches were updated on a regular basis and incorporated in the guideline to November 2013. Grey (unpublished literature) was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES The quality of evidence in this document was rated using the criteria described by the Canadian Task Force on Preventive Health Care (Table). BENEFITS, HARMS, AND COSTS These recommendations are expected to allow adequate management of women with fibroids and infertility, maximizing their chances of pregnancy by minimizing risks introduced by unnecessary myomectomies. Reducing complications and eliminating unnecessary interventions are also expected to decrease costs to the health care system. Summary Statements 1. Subserosal fibroids do not appear to have an impact on fertility; the effect of intramural fibroids remains unclear. If intramural fibroids do have an impact on fertility, it appears to be small and to be even less significant when the endometrium is not involved. (II-3) 2. Because current medical therapy for fibroids is associated with suppression of ovulation, reduction of estrogen production, or disruption of the target action of estrogen or progesterone at the receptor level, and it has the potential to interfere in endometrial development and implantation, there is no role for medical therapy as a stand-alone treatment for fibroids in the infertile population. (III) 3. Preoperative assessment of submucosal fibroids is essential to the decision on the best approach for treatment. (III) 4. There is little evidence on the use of Foley catheters, estrogen, or intrauterine devices for the prevention of intrauterine adhesions following hysteroscopic myomectomy. (II-3) 5. In the infertile population, cumulative pregnancy rates by the laparoscopic and the minilaparotomy approaches are similar, but the laparoscopic approach is associated with a quicker recovery, less postoperative pain, and less febrile morbidity. (II-2) 6. There are lower pregnancy rates, higher miscarriage rates, and more adverse pregnancy outcomes following uterine artery embolization than after myomectomy. (II-3) Studies also suggest that uterine artery embolization is associated with loss of ovarian reserve, especially in older patients. (III) Recommendations 1. In women with infertility, an effort should be made to adequately evaluate and classify fibroids, particularly those impinging on the endometrial cavity, using transvaginal ultrasound, hysteroscopy, hysterosonography, or magnetic resonance imaging. (III-A) 2. Preoperative assessment of submucosal fibroids should include, in addition to an assessment of fibroid size and location within the uterine cavity, evaluation of the degree of invasion of the cavity and thickness of residual myometrium to the serosa. A combination of hysteroscopy and transvaginal ultrasound or hysterosonography are the modalities of choice. (III-B) 3. Submucosal fibroids are managed hysteroscopically. The fibroid size should be < 5 cm, although larger fibroids have been managed hysteroscopically, but repeat procedures are often necessary. (III-B) 4. A hysterosalpingogram is not an appropriate exam to evaluate and classify fibroids. (III-D) 5. In women with otherwise unexplained infertility, submucosal fibroids should be removed in order to improve conception and pregnancy rates. (II-2A) 6. Removal of subserosal fibroids is not recommended. (III-D) 7. There is fair evidence to recommend against myomectomy in women with intramural fibroids (hysteroscopically confirmed intact endometrium) and otherwise unexplained infertility, regardless of their size. (II-2D) If the patient has no other options, the benefits of myomectomy should be weighed against the risks, and management of intramural fibroids should be individualized. (III-C) 8. If fibroids are removed abdominally, efforts should be made to use an anterior uterine incision to minimize the formation of postoperative adhesions. (II-2A) 9. Widespread use of the laparoscopic approach to myomectomy may be limited by the technical difficulty of this procedure. Patient selection should be individualized based on the number, size, and location of uterine fibroids and the skill of the surgeon. (III-A) 10. Women, fertile or infertile, seeking future pregnancy should not generally be offered uterine artery embolization as a treatment option for uterine fibroids. (II-3E).
International Journal of Gynecology & Obstetrics | 2012
Kimberly E. Liu; Allison Case; Anthony P. Cheung; Sony Sierra; Saleh AlAsiri; Belina Carranza-Mamane; Cathie Dwyer; James Graham; Jon Havelock; Robert Hemmings; Francis Lee; Ward Murdock; Vyta Senikas; Tannys D.R. Vause; Benjamin Chee-Man Wong
To improve awareness of the natural age‐related decline in female and male fertility with respect to natural fertility and assisted reproductive technologies (ART) and provide recommendations for their management, and to review investigations in the assessment of ovarian aging.
Journal of obstetrics and gynaecology Canada | 2014
Shannon Corbett; Doron Shmorgun; Paul Claman; Anthony P. Cheung; Sony Sierra; Belina Carranza-Mamane; Allison Case; Cathie Dwyer; James Graham; Jon Havelock; Sarah Healey; Robert Hemmings; Kimberly E. Liu; Tarek Motan; Ward Murdock; David S. Smithson; Tannys D.R. Vause; Benjamin Wong; Mathias Gysler
OBJECTIVE To review the clinical aspects of ovarian hyperstimulation syndrome and provide recommendations on its prevention. OPTIONS Preventative measures, early recognition, and prompt systematic supportive care will help avoid poor outcomes. OUTCOMES Establish guidelines to assist in the prevention of ovarian hyperstimulation syndrome, early recognition of the condition when it occurs, and provision of appropriate supportive measures in the correct setting. EVIDENCE Published literature was retrieved through searches of Medline, Embase, and the Cochrane Library from 2011 to 2013 using appropriate controlled vocabulary ([OHSS] ovarian hyperstimulation syndrome and: agonist IVF, antagonist IVF, metformin, HCG, gonadotropin, coasting, freeze all, agonist trigger, progesterone) and key words (ovarian hyperstimulation syndrome, ovarian stimulation, gonadotropin, human chorionic gonadotropin, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies published in English. There were no date restrictions. Searches were updated on a regular basis and incorporated in the guideline to February 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Summary Statements 1. The particular follicle-stimulating hormone formulation used for ovarian stimulation does not affect the incidence of ovarian hyperstimulation syndrome. (I) 2. Coasting may reduce the incidence of severe ovarian hyperstimulation syndrome. (III) 3. Coasting for longer than 3 days reduces in vitro fertilization pregnancy rates. (II-2) 4. The use of either luteinizing hormone or human chorionic gonadotropin for final oocyte maturation does not influence the incidence of ovarian hyperstimulation syndrome. (I) 5. There is no clear published evidence that lowering the human chorionic gonadotropin dose will result in a decrease in the rate of ovarian hyperstimulation syndrome. (III) 6. Cabergoline starting from the day of human chorionic gonadotropin reduces the incidence of ovarian hyperstimulation syndrome in patients at higher risk and does not appear to lower in vitro fertilization pregnancy rates. (II-2) 7. Avoiding pregnancy by freezing all embryos will prevent severe prolonged ovarian hyperstimulation syndrome in patients at high risk. (II-2) 8. Pregnancy rates are not affected when using gonadotropin-releasing hormone (GnRH) agonists in GnRH antagonist protocols for final egg maturation when embryos are frozen by vitrification for later transfer. (II-2) Recommendations 1. The addition of metformin should be considered in patients with polycystic ovarian syndrome who are undergoing in vitro fertilization because it may reduce the incidence of ovarian hyperstimulation syndrome. (I-A) 2. Gonadotropin dosing should be carefully individualized, taking into account the patients age, body mass, antral follicle count, and previous response to gonadotropins. (II-3B) 3. Cycle cancellation before administration of human chorionic gonadatropin is an effective strategy for the prevention of ovarian hyperstimulation syndrome, but the emotional and financial burden it imposes on patients should be considered before the cycle is cancelled. (III-C) 4. Gonadotropin-releasing hormone (GnRH) antagonist stimulation protocols are recommended in patients at high risk for ovarian hyperstimulation syndrome (OHSS). The risk of severe OHSS in patients on GnRH antagonist protocols who have a very robust ovarian stimulation response can be reduced by using a GnRH agonist as a substitute for human chorionic gonadotropin to trigger final oocyte maturation. (I-B) 5. A gonadotropin-releasing hormone (GnRH) antagonist protocol with a GnRH agonist trigger for final oocyte maturation is recommended for donor oocyte and fertility preservation cycles. (III-C) 6. Albumin or other plasma expanders at the time of egg retrieval are not recommended for the prevention of ovarian hyperstimulation syndrome. (I-E) 7. Elective single embryo transfer is recommended in patients at high risk for ovarian hyperstimulation syndrome. (III-C) 8. Progesterone, rather than human chorionic gonadotropin, should be used for luteal phase support. (I-A) 9. Outpatient culdocentesis should be considered for the prevention of disease progression in severe ovarian hyperstimulation syndrome. (II-2B).
Journal of obstetrics and gynaecology Canada | 2017
Savanie Maithripala; Ursula Durland; Jon Havelock; Sonya Kashyap; Jason Hitkari; Justin Tan; Mahmoud Iews; Sarka Lisonkova; Mohamed A. Bedaiwy
OBJECTIVE Parental carriers of balanced structural chromosomal rearrangements such as reciprocal or Robertsonian translocations are at increased risk of recurrent pregnancy loss (RPL) due to the production of gametes with unbalanced non-viable chromosome variants. As a purported means of improving reproductive outcomes in this population, IVF and preimplantation genetic diagnosis (PGD) have been introduced as an alternative to natural conception and prenatal diagnosis. In this study, we evaluate the prevalence and treatment choices of couples with structural chromosomal rearrangement referred to a tertiary care RPL clinic. In addition, we compare the two methods of management in terms of live birth rate. METHODS This is a retrospective chart review of 2321 couples who were referred to a highly specialized RPL clinic for ongoing clinical management between January 2005 and December 2013 (n = 23). Couples who pursued PGD through local fertility centres during this time were also included (n = 13). RESULTS Thirty-six couples (1.6%) were found to be parental carriers of a structural chromosomal rearrangement. In this cohort, couples were twice as likely to pursue natural conception compared with IVF with PGD. No significant differences were observed in live birth rate between PGD and clinical management (66.6% vs. 53.3%, P = 0.717). With PGD management, six live birth outcomes were observed, with an incidence of one birth in 5.63 years of follow-up. With clinical management, 24 live birth outcomes were observed, with an incidence of one birth in 4.09 years of follow-up. Mean time to live birth was 17.5 months and 23.3 months in clinical management and PGD, respectively. CONCLUSIONS Among couples presenting to a tertiary RPL clinic, parental carriers of structural chromosomal rearrangement and history of RPL are more likely to pursue natural conception over IVF and PGD. With regards to reproductive outcomes, no significant difference in miscarriage rate, time to live birth, or live birth rate was observed between couples who pursued PGD compared with expectant clinical management.
Journal of Minimally Invasive Gynecology | 2012
Caitlin Dunne; Jon Havelock
Sertoli-Leydig cell tumors (SLCT) are rare, comprising less than 0.5% of ovarian neoplasms. They are most often diagnosed in premenopausal women and may produce androgens, resulting in hirsuitism, voice deepening, frontal balding, terminal hair growth, and clitoromegaly. SLCT are malignant in 15%-20% of cases. We discuss a 25-year-old patient with persistent hyperandrogenemia. Noninvasive imaging cannot conclusively differentiate between SCLT and other diagnoses such as polycystic ovary syndrome, ovarian hyperthecosis, idiopathic hyperandrogenism, idiopathic hirsuitism, and 21-hydroxylase-deficient nonclassic adrenal hyperplasia. Selective ovarian vein sampling revealed a 15-fold greater testosterone production from the right ovary compared with the left, which guided appropriate surgical management.
Journal of Minimally Invasive Gynecology | 2018
Clara Q. Wu; Arianne Y. K. Albert; Sukainah Alfaraj; Omur Taskin; G.M. Alkusayer; Jon Havelock; Paul J. Yong; Catherine Allaire; Mohamed A. Bedaiwy
Controversy exists regarding surgical management of endometriomas in infertile women before in vitro fertilization (IVF) because growing evidence indicates that surgery may impair the ovarian response. The objective of the present systematic review and meta-analysis was to compare surgical and expectant management of endometriomas regarding IVF outcomes. Prospective and retrospective controlled studies were found via the Cochrane Library, Embase, and MEDLINE databases. Thirteen studies (1 randomized controlled trial and 12 observational studies, N = 2878) were pooled, and similar live birth rates were observed in the surgically and expectantly managed groups (odds ratio = 0.83; 95% confidence interval [CI], 0.56-1.22; p = .98). The clinical pregnancy rates (odds ratio = 0.83; 95% CI, 0.66-1.05; p = .86), the number of mature oocytes retrieved, and the miscarriage rates were not statistically different between study groups. However, the total number of oocytes retrieved was lower in the surgery group (mean difference = -1.51; 95% CI, -2.60 to -0.43; p = .02). Findings suggest that surgical management of endometriomas before IVF therapy yields similar live birth rates as expectant management. However, future properly designed randomized controlled trials are warranted.
Journal of obstetrics and gynaecology Canada | 2014
Shannon Corbett; Doron Shmorgun; Paul Claman; Anthony P. Cheung; Sony Sierra; Belina Carranza-Mamane; Allison Case; Cathie Dwyer; James Graham; Jon Havelock; Sarah Healey; Robert Hemmings; Kimberly E. Liu; Tarek Motan; Ward Murdock; David S. Smithson; Tannys D.R. Vause; Benjamin Wong; Mathias Gysler
Résultats : La littérature publiée a été récupérée par l’intermédiaire de recherches menées dans Medline, Embase et The Cochrane Library entre 2011 et 2013 au moyen d’un vocabulaire contrôlé (« ovarian hyperstimulation syndrome », « agonist IVF », « antagonist IVF », « metformin », « HCG », « gonadotropin », « coasting », « freeze all », « agonist trigger », « progesterone ») et de mots clés (« ovarian hyperstimulation syndrome », « ovarian stimulation », « gonadotropin », « human chorionic gonadotropin », « prevention ») appropriés. Les résultats ont été restreints aux analyses systématiques, aux études observationnelles et aux essais comparatifs randomisés / essais cliniques comparatifs publiés en anglais. Aucune restriction n’a été imposée en matière de date. Les recherches ont été mises à jour de façon régulière et ont été intégrées à la directive clinique jusqu’en février 2013.