Christophe Blockeel
Vrije Universiteit Brussel
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Human Reproduction | 2011
Paul Devroey; Nikolaos P. Polyzos; Christophe Blockeel
Published data indicate a significant increase in ovarian hyperstimulation syndrome globally. The occurrence of approximately three maternal deaths per 100,000 stimulated women has been reported, and extrapolation of these figures to a global situation would give an impressive number. The syndrome can be erased by applying ovarian stimulation using the combination of GnRH antagonist with GnRH agonist to trigger ovulation. In this case, the strategy is to freeze all of the oocytes or embryos for later use.
Reproductive Biomedicine Online | 2011
I. Van Vaerenbergh; Human M. Fatemi; Christophe Blockeel; L. Van Lommel; P. In’t Veld; Frans Schuit; Efstratios M. Kolibianakis; Paul Devroey; Claire Bourgain
Premature progesterone rise during gonadotrophin-releasing hormone (GnRH) antagonist cycles for IVF is a frequent phenomenon and has been associated with lower pregnancy and implantation rates. This study evaluated endometrial gene expression on the day of oocyte retrieval according to the concentration of serum progesterone on the day of human chorionic gonadotrophin (HCG) administration in GnRH-antagonist/recombinant FSH IVF cycles with fresh embryo transfer. Endometrial biopsies (n=14) were analysed with Affymetrix HG U133 Plus 2.0 Arrays. Patients were divided into three groups according to their progesterone serum concentration on the day of HCG administration: ≤ 0.9 ng/ml (group A), 1-1.5 ng/ml (group B) and >1.5 ng/ml (group C). Gene expression analysis showed a small number of significantly differentially expressed probe sets between groups A and B (five up/23 down in B) and a large difference between groups B and C (607 up/212 down; P ≤ 0.05, fold change ≥ 1.4). Validation was performed with quantitative real-time PCR on selected genes. As far as is known, this is the first study to demonstrate a distinct difference in endometrial gene expression profile between patients with a progesterone serum concentration above and below the threshold of 1.5 ng/ml on the day of HCG administration.
Reproductive Biomedicine Online | 2008
Christophe Blockeel; Valerie Schutyser; Anick De Vos; W. Verpoest; Michel De Vos; Catherine Staessen; Patrick Haentjens; Josiane Van der Elst; Paul Devroey
This randomized, controlled trial verifies whether patients with recurrent failed implantation benefit from preimplantation genetic diagnosis for aneuploidy, as compared with conventional assisted reproduction treatment procedures. Two hundred patients with recurrent failed implantation were randomized into two groups. A total of 139 patients underwent ovarian stimulation, and preimplantation genetic screening was performed in 72 patients. Analysis of chromosomes X, Y, 13, 16, 18, 21 and 22 was carried out using fluorescence in-situ hybridization in blastomeres of day-3 cleavage-stage embryos in the study group. The primary endpoint was implantation rate. Secondary endpoints were embryonic morphology and chromosomal status, number of transferred embryos and clinical pregnancy rate. With regard to the implantation rate, there was no significant difference between the study group (21.4%) and the control group (25.3%). The number of embryos transferred was significantly lower in the study group, namely 1.4 (SD 1.0) versus 2.1 (SD 1.0) in the control group (P < 0.05). The clinical pregnancy rate was not significantly different between the groups (25.0% in the study group versus 40.3% in the control group). It can be concluded that preimplantation genetic screening does not increase the implantation rates after IVF-intracytoplasmic sperm injection in women with repeated implantation failure.
Human Reproduction | 2012
Nikolaos P. Polyzos; Christophe Blockeel; W. Verpoest; M. De Vos; D. Stoop; Veerle Vloeberghs; Michel Camus; Paul Devroey; Herman Tournaye
STUDY QUESTION What is the effect of natural cycle IVF in women with poor ovarian response according to the new ESHRE definition for poor ovarian responders: the Bologna criteria? SUMMARY ANSWER Although natural cycle IVF is a promising treatment option for normal responders, poor ovarian responders, as described by the Bologna criteria, have a very poor prognosis and do not appear to experience substantial benefits with natural cycle IVF. WHAT IS KNOWN ALREADY Previous trials have shown that natural cycle IVF is an effective treatment for the general infertile population and might be an option for poor ovarian responders. However, none of the trials have examined the effect of natural cycle IVF in poor responders according to the Bologna criteria, the newly introduced definition by the ESHRE Working Group on Poor Ovarian Response Definition. In this trial, we examined the effect of natural cycle IVF in poor ovarian responders fulfilling the Bologna criteria. STUDY DESIGN, SIZE, DURATION In this retrospective cohort trial, 164 consecutive patients, undergoing 469 natural cycle IVFs between 2008 and 2011 were included. Patients were stratified as poor and normal responders: 136 (390 cycles) were poor ovarian responders according to the Bologna criteria, whereas 28 women (79 treatment cycles) did not fulfil the criteria and were considered as normal responders. PARTICIPANTS/MATERIALS, SETTING, METHODS All patients were monitored with hormonal analysis and ultrasound scan every second day, from Day 7 or 8 of the cycle onwards. When a follicle of >16 mm was observed, ovulation was triggered with 5000 IU of i.m. hCG and oocyte retrieval was performed 32 h later. MAIN RESULTS AND THE ROLE OF CHANCE Live birth rates in poor responders according to the Bologna criteria were significantly lower compared with the control group of women; the live birth rate per cycle was 2.6 versus 8.9%, P = 0.006 and the live birth rate per treated patient was 7.4 versus 25%, P = 0.005. In poor responders according to the Bologna criteria, live birth rates were consistently low and did not differ among different age groups (≤ 35 years, 36-39 years and ≥ 40 years), with a range from 6.8 to 7.9%. LIMITATIONS, REASONS FOR CAUTION A limitation of our analysis is its retrospective design; however, taking into account that we included only consecutive patients treated with exactly the same protocol, the likelihood of selection bias might be considerably limited. In addition, the control group in our study refers to women of younger age and therefore the promising results among patients who did not fulfil the Bologna criteria apply only to women of younger age. WIDER IMPLICATIONS OF THE FINDINGS Our trial suggests that although natural cycle IVF is a promising treatment option for younger normal responders, its potential is very limited to poor ovarian responders as described by the Bologna criteria, irrespective of patients age. This highlights the very poor prognosis of these women and therefore the urgent need for future trials to examine the effect of ovarian stimulation protocols in women with poor ovarian response as described by the Bologna criteria. STUDY FUNDING/COMPETING INTEREST(S) No funding was used. There are no competing interests to declare.
Human Reproduction | 2016
Panagiotis Drakopoulos; Christophe Blockeel; D. Stoop; Michel Camus; de Vos M; Herman Tournaye; N.P. Polyzos
STUDY QUESTION What is the impact of ovarian response on cumulative live birth rates (LBR) following utilization of all fresh and frozen embryos in women undergoing their first ovarian stimulation cycle, planned to undergo single embryo transfer (SET). SUMMARY ANSWER Cumulative LBR significantly increases with the number of oocytes retrieved. WHAT IS KNOWN ALREADY Several studies have addressed the issue of the optimal number of oocytes retrieved following controlled ovarian stimulation (COS) for IVF/ICSI and demonstrated that ovarian response is independently related to LBR following IVF/ICSI. The vast majority of studies pertained only to the outcome of the fresh IVF cycle and did not evaluate the cumulative LBR following the transfer of all fresh and frozen-thawed embryos after a single ovarian stimulation, which is the most meaningful outcome for the infertile patient. STUDY DESIGN, SIZE, DURATION This study is a large cohort analysis of retrospective data from January 2009 to December 2013 in a tertiary medical centre, at the Centre for Reproductive Medicine at the University Hospital of Brussels. PARTICIPANTS/MATERIALS, SETTING, METHODS This study included 1099 eligible consecutive women 18-40 years old undergoing their first IVF cycle and planned to undergo SET in their fresh cycle. All patients were treated with a conventional starting gonadotrophin dose of 150-225 IU recombinant FSH (rFSH) in a fixed GnRH antagonist protocol. Vitrification was used as cryopreservation method. To evaluate the impact of oocyte yield on fresh LBR and on cumulative LBR after utilization of all cryopreserved embryos, patients were categorized into four groups according to the number of oocytes retrieved: 1-3 (Group A), 4-9 (Group B), 10-15 (Group C) or >15 oocytes (Group D). MAIN RESULTS AND THE ROLE OF CHANCE Regarding LBR in the fresh IVF/ICSI cycles, unadjusted results did not show any significant difference when comparing either high (>15 oocytes) versus normal (10-15 oocytes) (P = 0.65), or normal (10-15) versus suboptimal (4-9 oocytes) responders (P = 0.2). LBR in the fresh cycles were significantly higher (P < 0.05) in high, normal and suboptimal responders when compared with the low ovarian responder group (1-3 oocytes). Moderate-severe ovarian hyperstimulation syndrome occurred in 11 out of 1099 patients (1%). The cumulative LBR significantly increased with the number of oocytes retrieved (χ(2) test for trend P < 0.001). High responders (>15 oocytes) demonstrated a significantly higher LBR not only versus poor (0-3 oocytes) (P < 0.001) and suboptimal (4-9) responders (P < 0.001), but also versus women with normal (10-15) ovarian response (P = 0.014). Finally, although suboptimal responders had a better outcome compared with poor ovarian responders (P = 0.002), this group had a significantly lower cumulative LBR compared with normal ovarian responders (P = 0.02). Multivariate logistic regression analysis showed that the ovarian response category remained an independent predictive factor (P < 0.001) for cumulative LBR. LIMITATIONS, REASONS FOR CAUTION This is a cohort analysis based on retrospective data collection. Despite our robust methodological approach, the presence of biases related to retrospective design cannot be excluded. High responders may inherently have had a better prognosis. In addition, we cannot provide any guidance for patients undergoing either multiple embryo transfers or treated with higher gonadotrophin doses. WIDER IMPLICATIONS OF THE FINDINGS Women undergoing COS for their first IVF/ICSI cycle and SET should be informed that, although the number of oocytes retrieved does not affect LBR in the fresh cycle, the higher the oocyte yield, the higher the probability to achieve a live birth after utilization of all cryopreserved embryos. Large cohort studies are needed in order to confirm our results of cumulative LBR in different ovarian stimulation settings with higher stimulation doses. STUDY FUNDING/COMPETING INTERESTS No external funding was used for this study. No conflicts of interest are declared.
Human Reproduction | 2013
Stamatina Iliodromiti; Christophe Blockeel; Kelton Tremellen; Richard Fleming; Herman Tournaye; Peter Humaidan; Scott M. Nelson
STUDY QUESTION Are clinical pregnancy rates satisfactory and the incidence of OHSS low after GnRH agonist trigger and modified intensive luteal support in patients with a high risk of ovarian hyperstimulation syndrome (OHSS)? SUMMARY ANSWER GnRH agonist trigger combined with 1500 IU hCG at the time of oocyte retrieval and subsequent estradiol and progesterone replacement in OHSS high-risk patients can facilitate fresh embryo transfer with high clinical pregnancy rates and a low risk of severe OHSS. WHAT IS KNOWN ALREADY Conventional luteal support packages are inadequate to facilitate a fresh transfer after a GnRH agonist trigger. A low dose of hCG (1500 IU) after oocyte aspiration can be used to replace the actions of early luteal LH to sustain implantation and the function of the early corpus luteum, although the level of risk of severe OHSS with this strategy is unclear. STUDY DESIGN, SIZE, DURATION This international multicentre retrospective case study, including 275 women at high risk of OHSS, was undertaken during the period January 2011-December 2012. PARTICIPANTS/MATERIALS, SETTING, METHODS Women were identified as at high risk of OHSS, based on IVF response, ovarian reserve characteristics and previous history of having had treatment, in three clinical IVF centres in UK, Belgium and Australia. All three centres used a GnRH agonist trigger followed by one bolus of 1500 IU hCG 1h after oocyte retrieval. Moreover, the luteal phase was supported with daily vaginal progesterone and twice daily estradiol valerate. MAIN RESULTS AND THE ROLE OF CHANCE A total of 275 autologous cycles with fresh transfer were undertaken in a cohort of high-risk women as defined by baseline characteristics [median (interquartile range)]: age 31.6 (29-35) years, antral follicle count median 25 (18-34) and anti-Müllerian hormone median 49.1 pmol/l (35.2-69.3). At the end of stimulation, the peak estradiol median of 12 000 pmol/l (9400-15 914) and the mean oocyte yield of 17.8 ± 8.4 confirmed a high response. The overall clinical pregnancy rate was 41.8% per cycle started, with only two cases of severe OHSS reported (0.72%). No significant differences in clinical pregnancy rates between centres were identified. LIMITATIONS, REASONS FOR CAUTION This is a retrospective study and future randomized controlled trials will be able to compare whether these outcomes can be improved upon by either segmentation of the stimulation cycle and embryo transfer or alternative aggressive luteal support strategies. WIDER IMPLICATIONS OF THE FINDINGS In women who are undergoing ovarian stimulation and who develop an excessive ovarian response, the use of a GnRH agonist trigger combined with modified luteal support can provide the opportunity to proceed to fresh embryo transfer with adequate clinical pregnancy rates. However, this procedure will not completely eliminate the risk of OHSS and for women with an extreme ovarian response or with significant comorbidity, where the possibility of severe OHSS is unacceptable, we recommend GnRH agonist trigger followed by a freeze-all policy to completely avoid OHSS.
Reproductive Biomedicine Online | 2014
Nikolaos P. Polyzos; Milie Nwoye; Roberta Corona; Christophe Blockeel; D. Stoop; Patrick Haentjens; Michel Camus; Herman Tournaye
This retrospective study determined the efficacy of ovarian stimulation for IVF/intracytoplasmic sperm injection (ICSI) in poor ovarian responders fulfilling the Bologna criteria for poor ovarian response and identified predictors of live birth rates. Overall, 485 patients undergoing 823 ovarian stimulation cycles for IVF/ICSI with maximum gonadotrophin dose (≥ 300 IU) between January 2009 and December 2011 were included. Patients were considered eligible, irrespective of the treatment protocol, if they were classified as poor responders based on the recently developed definition for poor ovarian response by the European Society of Human Reproduction and Embryology, the Bologna criteria. Live birth rates did not significantly differ between women aged <40 and women aged ≥ 40 years either per cycle (7.1 versus 5.2%, OR 1.38, 95% CI 0.77-2.46) or per patient (11.6 versus 8.8%, OR 1.36, 95% CI 0.75-2.46). In logistic regression analysis, the number of oocytes retrieved was the only variable significantly associated with live births (OR 1.92, 95% CI 1.03-3.55 for >3 versus 1-3 oocytes). Bologna poor responders demonstrate very low live birth rates, irrespective of age and treatment protocol used. An increase in the number of oocytes retrieved is an independent variable related to live birth rates.
Fertility and Sterility | 2013
Human M. Fatemi; Nikolaos P. Polyzos; Inge Van Vaerenbergh; Claire Bourgain; Christophe Blockeel; Birgit Alsbjerg; E.G. Papanikolaou; Peter Humaidan
OBJECTIVE To assess endocrine differences during early luteal phase according to mode of triggering final oocyte maturation with or without luteal phase support (LPS). DESIGN A prospective randomized study. SETTING University center for reproductive medicine. PATIENT(S) Four oocyte donors each underwent four consecutive cycles. INTERVENTION(S) To avoid interpatient variation, each donor underwent the same stimulation regimen. However, different modes of triggering final oocyte maturation and LPS were administered: A) 10,000 IU hCG and standard LPS; B) GnRH agonist (GnRHa; 0.2 mg triptorelin), and 35 hours later 1,500 IU hCG, and standard LPS; C) GnRH agonist (0.2 mg triptorelin) and standard LPS; and D) GnRH agonist (0.2 mg triptorelin) without LPS. MAIN OUTCOME MEASURE(S) Blood sampling was performed on the day of ovulation trigger, ovulation trigger + 1 day, and ovum pick-up + 5 days. Serum E2, FSH, LH, and P were measured. RESULT(S) The early luteal phase steroid levels following GnRHa trigger and modified luteal phase support (B) were similar to those seen after hCG trigger (A). However, significant differences were seen between groups A and B compared with C and D, as well as between groups C and D. CONCLUSION(S) Administration of a single bolus of GnRHa effectively induced LH and FSH surges in oocyte donors stimulated with recombinant FSH and cotreated with a GnRH antagonist. However, gonadotropin and steroid levels differed significantly according to the type of luteal phase support used after GnRHa trigger. EUROPEAN COMMUNITY CLINICAL TRIAL SYSTEM (EUDRACT) NUMBER 2009-009429-26.
Human Reproduction Update | 2012
Nikolaos P. Polyzos; A. Zavos; A. Valachis; C. Dragamestianos; Christophe Blockeel; D. Stoop; E.G. Papanikolaou; Herman Tournaye; Paul Devroey; Ioannis E. Messinis
BACKGROUND Although several randomized controlled trials (RCTs) have examined the effect of misoprostol prior to hysteroscopy for cervical dilatation, no solid conclusion has been reached. We therefore set out to perform a meta-analysis of RCTs. METHODS We searched MEDLINE, the ISI Web of Science and the Cochrane Library to identify RCTs comparing misoprostol versus placebo or control prior to hysteroscopy. No restrictions on language or time were applied. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated for all dichotomous outcomes, whereas mean differences (MDs) and 95% CIs were calculated for continuous outcomes using the Mantel-Haenszel or DerSimonian-Laird model according to the heterogeneity. RESULTS Of the initial 141 potentially relevant articles that were retrieved, 21 RCTs involving 1786 patients were included in the meta-analysis. Subgroup analyses were performed according to menopausal status and according to whether diagnostic or operative hysteroscopy was performed. Premenopausal women treated with misoprostol had a significantly lower risk for further cervical dilatation in the diagnostic setting [RR (95% CI): 0.56 (0.34-0.92)] and a significantly lower risk for cervical laceration in the operative setting [RR (95% CI): 0.22 (0.09-0.54)], compared with placebo. In contrast, post-menopausal patients did not experience any clear benefit from misoprostol compared with placebo regarding the need for further cervical dilatation [RR (95% CI): 0.99 (0.76-1.30)] and the cervical laceration rate [RR (95% CI): 1.15 (0.40-3.29)]. In addition, the mean cervical width prior to hysteroscopy was significantly higher in premenopausal women treated with misoprostol compared with placebo [MD (95% CI): 2.47 mm (1.81-3.13)] but did not differ among post-menopausal patients [MD (95% CI): 0.39 mm (-0.42 to 1.21)]. CONCLUSIONS Misoprostol prior to hysteroscopy appears to facilitate an easier and uncomplicated procedure only in premenopausal women.
Reproductive Biomedicine Online | 2013
Richard Fleming; Frank J. Broekmans; C. Calhaz-Jorge; L. Dracea; H. Alexander; A. Nyboe Andersen; Christophe Blockeel; Julian Jenkins; Bruno Lunenfeld; Peter Platteau; Johan Smitz; D. de Ziegler
The ability to predict the response potential of women to ovarian stimulation may allow the development of individualized ovarian stimulation protocols. This tailored approach to ovarian stimulation could reduce the incidence of ovarian hyperstimulation syndrome in women predicted to have an excessive response to stimulation or could improve pregnancy outcomes in women classed as poor responders. Namely, variation of the type of gonadotrophin-releasing hormone (GnRH) analogue or the form and dosage of gonadotrophin used for stimulation could be adjusted according to an individuals response potential. The serum concentration of anti-Müllerian hormone (AMH) is established as a reliable marker of ovarian reserve, with decreasing concentrations correlated with reduced response potential. This review examines the current evidence evaluating individualized ovarian stimulation protocols using AMH concentration as a predictive marker of ovarian response. The rationale behind why specific treatment protocols based on individual response potential may be more suitable is also discussed. Based on current evidence, it appears that the use of AMH serum concentrations to predict ovarian response and optimize treatment strategies is a promising approach for improving pregnancy outcomes in women undergoing ovarian stimulation. However, prospective randomized controlled trials evaluating this approach are needed before any firm conclusions can be drawn.