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Dive into the research topics where E.G. Papanikolaou is active.

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Featured researches published by E.G. Papanikolaou.


Fertility and Sterility | 2009

How to improve the probability of pregnancy in poor responders undergoing in vitro fertilization: a systematic review and meta-analysis

Dimitra Kyrou; Efstratios M. Kolibianakis; Christos A. Venetis; E.G. Papanikolaou; J. Bontis; Basil C. Tarlatzis

OBJECTIVE To systematically review the literature to identify randomized controlled trials, which evaluate interventions aiming to improve the probability of pregnancy in poor responders undergoing in vitro fertilization (IVF). DESIGN Systematic review and meta-analysis. SETTING University-based hospital. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Pregnancy rate. RESULT(S) Twenty-two eligible randomized controlled trials were identified that evaluated in total 15 interventions to increase pregnancy rates in poor responders. Based on limited evidence, the only interventions that appear to increase the probability of pregnancy were the addition of GH to ovarian stimulation (odds ratio for live birth: 5.22, confidence interval: 95% 1.09-24.99) and the performance of embryo transfer on day 2 compared with day 3 (ongoing pregnancy rate: 27.7% vs. 16.3%, respectively; difference: +11.4, 95% confidence interval: +1.6 to +21.0). CONCLUSION(S) Insufficient evidence exists to recommend most of the treatments proposed to improve pregnancy rates in poor responders. Currently, there is some evidence to suggest that addition of GH, as well as performing embryo transfer on day 2 versus day 3, appear to improve the probability of pregnancy.


BMJ | 2010

Obstetric outcomes after treatment of periodontal disease during pregnancy: systematic review and meta-analysis

Nikolaos P. Polyzos; Ilias P. Polyzos; Apostolos Zavos; Antonis Valachis; Davide Mauri; E.G. Papanikolaou; Spyridon Tzioras; Daniel Weber; Ioannis E. Messinis

Objective To examine whether treatment of periodontal disease with scaling and root planing during pregnancy is associated with a reduction in the preterm birth rate. Design Systematic review and meta-analysis of randomised controlled trials. Data sources Cochrane Central Trials Registry, ISI Web of Science, Medline, and reference lists of relevant studies to July 2010; hand searches in key journals. Study selection Randomised controlled trials including pregnant women with documented periodontal disease randomised to either treatment with scaling and root planing or no treatment. Data extraction Data were extracted by two independent investigators, and a consensus was reached with the involvement a third. Methodological quality of the studies was assessed with the Cochrane’s risk of bias tool, and trials were considered either high or low quality. The primary outcome was preterm birth (<37 weeks). Secondary outcomes were low birthweight infants (<2500 g), spontaneous abortions/stillbirths, and overall adverse pregnancy outcome (preterm birth <37 weeks and spontaneous abortions/stillbirths). Results 11 trials (with 6558 women) were included. Five trials were considered to be of high methodological quality (low risk of bias), whereas the rest were low quality (high or unclear risk of bias). Results among low and high quality trials were consistently diverse; low quality trials supported a beneficial effect of treatment, and high quality trials provided clear evidence that no such effect exists. Among high quality studies, treatment had no significant effect on the overall rate of preterm birth (odds ratio 1.15, 95% confidence interval 0.95 to 1.40; P=0.15). Furthermore, treatment did not reduce the rate of low birthweight infants (odds ratio 1.07, 0.85 to 1.36; P=0.55), spontaneous abortions/stillbirths (0.79, 0.51 to 1.22; P=0.28), or overall adverse pregnancy outcome (preterm births <37 weeks and spontaneous abortions/stillbirths) (1.09, 0.91 to 1.30; P=0.34). Conclusion Treatment of periodontal disease with scaling and root planing cannot be considered to be an efficient way of reducing the incidence of preterm birth. Women may be advised to have periodical dental examinations during pregnancy to test their dental status and may have treatment for periodontal disease. However, they should be told that such treatment during pregnancy is unlikely to reduce the risk of preterm birth or low birthweight infants.


Human Reproduction | 2013

GnRHa trigger and individualized luteal phase hCG support according to ovarian response to stimulation: two prospective randomized controlled multi-centre studies in IVF patients

Peter Humaidan; Nikolaos P. Polyzos; Birgit Alsbjerg; Karin Erb; Aage Mikkelsen; Helle Olesen Elbaek; E.G. Papanikolaou; Claus Yding Andersen

STUDY QUESTION Does a GnRH agonist (GnRHa) trigger followed by a bolus of 1.500 IU hCG in a group of patients at risk of ovarian hyperstimulation syndrome (OHSS) reduce the OHSS incidence compared with hCG trigger? SUMMARY ANSWER A GnRHa trigger followed by early luteal hCG support with one bolus of 1.500 IU hCG appears to reduce OHSS in patients at risk of OHSS; however, in a low-risk group a second bolus of 1.500 IU hCG induced two cases of late onset OHSS. WHAT IS KNOWN ALREADY A GnRHa trigger is an alternative to hCG in GnRH antagonist co-treated cycles. STUDY DESIGN, SIZE, DURATION Two RCTs were performed in four Danish IVF units. A total of 446 patients were assessed for eligibility and 390 patients were enrolled in the study from January 2009 until December 2011. The primary outcome of the study was OHSS incidence in the group at risk of OHSS. PARTICIPANTS/MATERIALS, SETTING, METHODS Patients received a fixed dose of recombinant human FSH for the first 4 days. On the day of triggering, patients were assessed for their risk of OHSS based on the total number of follicles ≥11 mm diameter, and were classified as being at risk of OHSS when the total number of follicles ≥11 mm was between 15 and 25 and at low risk of OHSS when the total number of follicles ≥11 mm was ≤14. Two separate randomization lists were used for each of the OHSS risk groups. Women at risk of OHSS were allocated (RCT 1) to either: Group A (n = 60), ovulation triggering with a bolus of 0.5 mg buserelin (GnRHa) s.c. followed by a single bolus of 1.500 IU hCG s.c. after the oocyte retrieval-or: Group B (n = 58): 5.000 IU hCG. Similarly, women at low risk of OHSS were allocated (RCT 2) to receive either: Group C (n = 125), a bolus of 0.5 mg buserelin s.c., followed by a bolus of 1.500 IU hCG s.c. after oocyte retrieval and a second bolus of 1.500 IU hCG on the day of oocyte retrieval +5-or: Group D (n = 141), 5.000 IU hCG. Groups C and D were included in order to obtain preliminary data. MAIN RESULTS AND THE ROLE OF CHANCE In women at risk of OHSS (RCT 1) (15-25 follicles) no OHSS case was seen in Group A (GnRHa trigger and one bolus of 1.500 IU hCG), whereas two cases of moderate late-onset OHSS occurred in group B (3.4%), (P = 0.24). In contrast, in women at a low risk of OHSS (RCT 2) (≤14 follicles) two cases of late-onset OHSS occurred in Group C (GnRHa trigger and two boluses of 1.500 IU hCG), whereas no OHSS case was encountered in Group D (P = 0.22). LIMITATIONS, REASONS FOR CAUTION Although the first RCT was powered to include 168 patients at risk of OHSS (15-25 follicles ≥11 mm) randomized to either GnRHa trigger or hCG trigger, the trial was prematurely discontinued when a total of 118 patients at risk of OHSS were randomized. In addition the second RCT in the OHSS low-risk group was designed as a feasibility study to assess the incidence of OHSS after GnRHa trigger and dual hCG administration versus 5.000 IU hCG. No power calculation was performed for this trial. In addition, there was a lack of blinding in the RCTs. WIDER IMPLICATIONS OF THE FINDINGS Although a non-significant result, one bolus of 1.500 IU hCG after GnRHa trigger tended to reduce the OHSS rate in patients with 15-25 follicles ≥11 mm as well as secure the ongoing pregnancy rate. In contrast, in patients at low risk of OHSS the administration of two boluses of 1.500 IU hCG after GnRHa trigger should be avoided as it may induce OHSS.


Fertility and Sterility | 2011

A novel method of luteal supplementation with recombinant luteinizing hormone when a gonadotropin-releasing hormone agonist is used instead of human chorionic gonadotropin for ovulation triggering: a randomized prospective proof of concept study

E.G. Papanikolaou; W. Verpoest; Human M. Fatemi; Basil C. Tarlatzis; Paul Devroey; Herman Tournaye

This pilot study investigates the role of luteal supplementation with recombinant LH in an attempt to reverse the poor reproductive outcome previously noticed after GnRH-agonist triggering of final oocyte maturation for IVF. Similar implantation rates were achieved with the novel recombinant LH luteal supplementation scheme compared with the standard luteal P protocol (25.0% vs. 26.7%, respectively). No cases of ovarian hyperstimulation syndrome (OHSS) were noticed in either group.


Human Reproduction | 2010

GnRHa to trigger final oocyte maturation: a time to reconsider

Peter Humaidan; E.G. Papanikolaou; Basil C. Tarlatzis

Recently GnRH antagonist protocols for the prevention of a premature LH surge were introduced, allowing final oocyte maturation to be triggered with a single bolus of a GnRH agonist (GnRHa). GnRHa is as effective as hCG for the induction of ovulation, and apart from the LH surge a FSH surge is also induced. Until recently, prospective randomized studies reported a poor clinical outcome when GnRHa was used to trigger final oocyte maturation in IVF/ICSI antagonist protocols, presumably due to a luteal phase deficiency, despite standard luteal phase supplementation with progesterone and estradiol. As GnRHa triggering of final oocyte maturation could possess advantages over hCG triggering in terms of a reduced if not eliminated risk of ovarian hyperstimulation syndrome (OHSS) and the retrieval of more mature oocytes, the challenge has been to rescue the luteal phase. In the literature now several studies report a luteal phase rescue with a reproductive outcome comparable to that of hCG induced final oocyte maturation. Although more research is needed, GnRHa triggering is now a valid alternative with potential benefits.


Reproductive Biomedicine Online | 2012

The luteal phase after GnRH-agonist triggering of ovulation: present and future perspectives

Peter Humaidan; E.G. Papanikolaou; Dimitra Kyrou; Birgit Alsbjerg; Nikos Polyzos; Paul Devroey; Human M. Fatemi

In stimulated IVF/intracytoplasmic sperm injection cycles, the luteal phase is disrupted, necessitating luteal-phase supplementation. The most plausible reason behind this is the ovarian multifollicular development obtained after ovarian stimulation, resulting in supraphysiological steroid concentrations and consecutive inhibition of LH secretion by the pituitary via negative feedback at the level of the hypothalamic-pituitary axis. With the introduction of the gonadotrophin-releasing hormone-(GnRH) antagonist, an alternative to human chorionic gonadotrophin triggering of final oocyte maturation is the use of GnRH agonist (GnRHa) which reduces or even prevents ovarian hyperstimulation syndrome (OHSS). Interestingly, the current regimens of luteal support after HCG triggering are not sufficient to secure the early implanting embryo after GnRHa triggering. This review discusses the luteal-phase insufficiency seen after GnRHa triggering and the various trials that have been performed to assess the most optimal luteal support in relation to GnRHa triggering. Although more research is needed, GnRHa triggering is now an alternative to HCG triggering, combining a significant reduction in OHSS with high ongoing pregnancy rates.


Human Reproduction | 2008

Flexible GnRH antagonist versus flare-up GnRH agonist protocol in poor responders treated by IVF: a randomized controlled trial

Trifon G. Lainas; Ioannis A. Sfontouris; E.G. Papanikolaou; John Zorzovilis; George K. Petsas; George T. Lainas; Efstratios M. Kolibianakis

BACKGROUND Although initial studies in poor responders using GnRH antagonists have reported encouraging results, they are limited in number, only a few of them are prospective, while the majority is characterized by limited power to detect a clinically important difference. METHODS A randomized controlled trial was performed in patients with one or more previous failed IVF cycles in which five or less oocytes were retrieved, using > or =300 IU of gonadotrophins/day. Patients were randomized by computer-generated list and treated by either the flare-up GnRH agonist protocol (n = 90) or a flexible GnRH antagonist protocol (n = 180). RESULTS Ongoing pregnancy rate, the primary outcome measure, was significantly higher in the antagonist group compared with the agonist group (12.2 versus 4.4%, P< 0.048; difference 7.8%, 95% CI: 0.2 to 14.0). Estradiol levels on the day of hCG administration were lower in the antagonist protocol [median (interquartile range): 572 (325-839) versus 727 (439-1029) pg/ml, P = 0.018]. Clinical and biochemical pregnancy rates, fertilization and implantation rates, as well as the number of oocytes retrieved, the number of mature oocytes present, the stimulation period and the gonadotrophin dosage were not significantly different between the two groups compared. CONCLUSIONS The flexible GnRH antagonist protocol is associated with significantly higher ongoing pregnancy rates compared with the flare-up GnRH agonist protocol in poor responders.


Human Reproduction | 2012

GnRH-agonist versus GnRH-antagonist IVF cycles: is the reproductive outcome affected by the incidence of progesterone elevation on the day of HCG triggering? A randomized prospective study

E.G. Papanikolaou; George Pados; Grigoris F. Grimbizis; E. Bili; L. Kyriazi; Nikolaos P. Polyzos; Peter Humaidan; Herman Tournaye; Basil C. Tarlatzis

BACKGROUND In view of the current debate concerning possible differences in efficacy between the two GnRH analogues used in IVF stimulated cycles, the current study aimed to explore whether progesterone control in the late follicular phase differs when GnRH antagonist is used as compared with GnRH agonist, and if so, to what extent the progesterone rise affects the probability of pregnancy. METHODS Overall 190 patients were randomized: 94 in the GnRH-agonist group and 96 in the GnRH-antagonist group. The GnRH-agonist long protocol started on Day 21 of the preceding cycle with intranasal buserelin (600 mg per day). The GnRH-antagonist protocol started on Day 6 of the stimulation with ganirelix or cetrorelix (each 0.25 mg). All blood samples were analysed with the Elecsys analyzer. An intention-to-treat analysis was applied. RESULTS A progesterone rise >1.5 ng/ml was noticed in 23.0% of the antagonist group, comparable with 24.1% incidence within the agonist group. Per patient randomized, delivery rates were also comparable: 28.1% in the antagonist group and 24.5% in the agonist group (odds ratio = 1.21, 95% confidence interval: 0.63-2.31, P= 0.56). However, there was a reduction in delivery rates when progesterone exceeded the threshold of 1.5 ng/ml, both in the agonist group (9.5 versus 31.8%, P= 0.03) and in the antagonist group (14.3 versus 34.3%, P= 0.07). CONCLUSIONS Although the incidence of a progesterone rise was similar between the two analogues, our findings reconfirm previous observations that insufficient progesterone control (>1.5 ng/ml) on the day of ovulation triggering is related to poor delivery rates in both protocols. The current study has shown that the reproductive outcomes with the two GnRH analogues are comparable. Possible modes of action to circumvent late follicular progesterone rise should be explored. TRIAL REGISTRATION NUMBER NCT01191710.


Reproductive Biomedicine Online | 2006

Aromatase inhibitors in ovarian stimulation for IVF/ICSI: a pilot study

W. Verpoest; Efstratios M. Kolibianakis; E.G. Papanikolaou; Johan Smitz; André Van Steirteghem; Paul Devroey

This prospective randomized pilot study was aimed at investigating the effect of the novel addition of aromatase inhibitors to an ovarian stimulation protocol for IVF or intracytoplasmic sperm injection, on endocrine parameters including serum androgen, oestrogen, progesterone, LH and FSH concentrations. The patients were randomized to receiving letrozole (group A; n = 10), versus no letrozole (group B; n = 10) in an ovarian stimulation protocol with recombinant FSH 150 IU/day starting on day 2 of the cycle, and gonadotrophin-releasing hormone antagonist 0.25 mg/day starting on day 6 of the cycle. Median LH concentrations were significantly higher (P < 0.01) in group A versus group B during letrozole administration. Median serum oestradiol concentrations were lower in group A versus group B, and median serum FSH, testosterone and androstenedione concentrations were higher in group A versus group B, throughout the follicular phase, without reaching significance. Median endometrial thickness was significantly higher (P < 0.05) in group A versus group B on the day of human chorionic gonadotrophin administration. Pregnancies were achieved. This pilot study supports the idea that aromatase inhibitors can contribute to normal potential of implantation and follicular response, without having negative anti-oestrogenic effects.


Human Reproduction | 2008

Estrogen addition to progesterone for luteal phase support in cycles stimulated with GnRH analogues and gonadotrophins for IVF: a systematic review and meta-analysis

Efstratios M. Kolibianakis; Christos A. Venetis; E.G. Papanikolaou; K. Diedrich; Basil C. Tarlatzis; G. Griesinger

BACKGROUND The purpose of the present systematic review and meta-analysis was to examine whether the probability of pregnancy is increased by adding estrogen to progesterone for luteal phase support in patients treated by in vitro fertilization (IVF). METHODS A literature search covering MEDLINE, EMBASE, CENTRAL, meeting proceedings and reference lists of published articles was performed to identify relevant RCTs. Data were extracted for meta-analysis yielding pooled relative risks (RR) and 95% confidence intervals (CI). Sensitivity analyses by including studies with pseudo-randomization or unclear method of randomization were also performed (n=1141 patients in total). RESULTS Four RCTs (n=587 patients) were eligible for inclusion. No statistically significant differences were present between patients who received a combination of progesterone and estrogen for luteal support when compared with those who received only progesterone, in terms of positive hCG rate (RR: 1.02, 95% CI: 0.87-1.19), clinical pregnancy rate (RR: 0.94, 95% CI: 0.78-1.13) and live birth rate (RR: 0.96, 95% CI: 0.77-1.21) per woman randomized. These results did not materially differ in the sensitivity analyses performed. CONCLUSIONS The currently available evidence suggests that the addition of estrogen to progesterone for luteal phase support does not increase the probability of pregnancy in IVF. However, there is an obvious need for further RCTs that will assess, with more confidence, the effect of estrogen addition to progesterone during the luteal phase on the probability of pregnancy.

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Paul Devroey

Vrije Universiteit Brussel

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Herman Tournaye

Free University of Brussels

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Efstratios M. Kolibianakis

Aristotle University of Thessaloniki

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Basil C. Tarlatzis

Aristotle University of Thessaloniki

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Human M. Fatemi

Vrije Universiteit Brussel

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Michel Camus

Vrije Universiteit Brussel

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W. Verpoest

Free University of Brussels

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