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Dive into the research topics where Konstantinos Zikopoulos is active.

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Featured researches published by Konstantinos Zikopoulos.


Reproductive Biomedicine Online | 2004

Live delivery rates in subfertile women with Asherman's syndrome after hysteroscopic adhesiolysis using the resectoscope or the Versapoint system

Konstantinos Zikopoulos; Efstratios M. Kolibianakis; Peter Platteau; Luc de Munck; Herman Tournaye; Paul Devroey; Michel Camus

The purpose of this study was to report on a 10-year experience in the treatment of subfertile women with intrauterine adhesions using the resectoscope or the Versapoint system. Forty-six subfertile women with stage I (n = 6), stage II (n = 25) and stage III (n = 15) intrauterine adhesions underwent adhesiolysis with the use of the resectoscope (n = 21) or the Versapoint system (n = 26). Synechiolysis was successful in 43 women (93.5%) after the first attempt. In 13 out of 14 women (92.9%) with oligo/amenorrhoea at presentation, restoration of menses was reported after adhesiolysis (Versapoint: 9/9, resectoscope: 4/5). Overall live delivery rates according to stage of intrauterine adhesions were 33.3, 44.4 and 46.7% for stages I, II and III respectively. Similar cumulative delivery rates were achieved in patients with no additional infertility factors who attempted to conceive naturally after adhesiolysis using the Versapoint (71.7%) or the resectoscope (60%). Ten gestations ended in preterm delivery (50%), while in two of the women who delivered, a hysterectomy was performed due to placenta accreta. In conclusion, hysteroscopic adhesiolysis offers a real chance of parenthood in a substantial proportion of infertile couples either by using the Versapoint system or the resectoscope.


Reproductive Biomedicine Online | 2004

Endometrial thickness cannot predict ongoing pregnancy achievement in cycles stimulated with clomiphene citrate for intrauterine insemination

Efstratios M. Kolibianakis; Konstantinos Zikopoulos; Human M. Fatemi; Kaan Osmanagaoglu; J Evenpoel; A. Van Steirteghem; Paul Devroey

To date, limited data exist concerning the relation between endometrial thickness on the day of human chorionic gonadotrohin (HCG) administration and ongoing pregnancy achievement in cycles stimulated with clomiphene citrate for intrauterine insemination (IUI). In a prospective study, 168 couples were stimulated with clomiphene citrate from day 3 to day 7 of the cycle and endometrial thickness was assessed by ultrasound three times on the day of ovulation triggering. Ovulation was induced with HCG as soon as >/=1 follicle of >/=17 mm was present at ultrasound independently of endometrial thickness. IUI was performed 36 h after HCG administration. The main outcome measure was ongoing pregnancy. No difference was observed in endometrial thickness between patients who did or did not achieve an ongoing pregnancy (7.6 +/- 0.3 versus 7.6 +/- 0.2 respectively; P = 0.7). No discriminative ability of endometrial thickness on the achievement of ongoing pregnancy could be shown by receiver operating characteristic (ROC) curve analysis (area under the ROC curve 0.51, 95% CI: 0.44-0.59). In conclusion, endometrial thickness cannot predict ongoing pregnancy achievement in IUI cycles stimulated with clomiphene citrate.


Reproductive Biomedicine Online | 2013

Open versus closed oocyte vitrification system: a prospective randomized sibling-oocyte study

Achilleas Papatheodorou; Pierre Vanderzwalmen; Yannis Panagiotidis; Nikolaos Prapas; Konstantinos Zikopoulos; Ioannis Georgiou; Yannis Prapas

Vitrification has been successfully applied in the cryopreservation of oocytes and embryos. It can be achieved either by direct (open system) or indirect (closed system) contact with liquid nitrogen. Unlike embryo vitrification, few reports have been published regarding oocyte vitrification in closed systems. In order to validate the effectiveness of a closed and aseptic vitrification approach for oocyte cryopreservation, a prospective, randomized study was performed. Sibling oocytes donated from the same donor were randomly and equally assigned into closed or open vitrification groups. A total of 75 vitrification-warming cycles were performed in each group. Apart from the survival rate (82.9% versus 91.0%, P<0.05), no statistically significant differences were observed in pregnancy (β-human chorionic gonadotrophin positive) (42.7% versus 33.3%), clinical pregnancy (36.0% versus 28.0%), implantation (13.8% versus 10.1%), ongoing pregnancy (33.3% versus 24.0%) and live birth (36.0% versus 24.0%) rates between the closed and open groups, and 27 and 18 healthy babies were born, respectively. This study shows that the replacement of the open vitrification system by a closed system has no impact on clinical pregnancy and implantation rates. Therefore, the closed vitrification system provides an aseptic alternative to the open method for oocyte vitrification.


Andrologia | 2012

Dramatic reduction in sperm parameters following bariatric surgery: report of two cases.

Leandros Lazaros; E. Hatzi; S. Markoula; Atsushi Takenaka; Nikolaos Sofikitis; Konstantinos Zikopoulos; Ioannis Georgiou

Severe obesity constitutes the main public health crisis of the industrialised world. Bariatric surgery has been proposed as the most efficient treatment of obesity. In this study, we report the potential effects of bariatric surgery on semen parameters in male partners of couples undergoing assisted reproduction. These patients had been tested in the context of infertility treatment in two consecutive cycles before and after bariatric surgery. A marked reduction in sperm parameters was observed in a period of twelve to eighteen months after surgery. This unfavourable effect had also remarkable effects on the assisted reproduction outcome, necessitating the counselling of patients before bariatric surgery.


Andrologia | 2008

Evidence for association of sex hormone-binding globulin and androgen receptor genes with semen quality

Leandros Lazaros; Nectaria Xita; Apostolos Kaponis; Konstantinos Zikopoulos; Nikolaos Sofikitis; Ioannis Georgiou

The roles of androgen receptor AR(CAG)n gene polymorphisms and sex hormone‐binding globulin SHBG(TAAAA)n gene polymorphisms on semen quality were studied. One hundred fourteen men were included in the study: 85 with normal sperm count and 29 oligospermic. The genotype analysis, on DNA extracted from spermatozoa, revealed five SHBG(TAAAA)n alleles with 6–10 repeats and 18 AR(CAG)n alleles with 12–32 repeats. The SHBG allelic distribution showed that in men with normal sperm count and motility, those with short SHBG alleles had higher sperm concentration than men with long SHBG alleles (P = 0.039). As concerns AR(CAG)n polymorphisms, men with short AR alleles had lower sperm motility compared to those with long AR alleles (P < 0.001) in both total study population and normal sperm count men. The synergistic effect analysis of the two polymorphisms revealed an association between sperm motility (P = 0.036), because of the effect of AR(CAG)n polymorphism on sperm motility. In conclusion, long AR alleles were found to be associated with higher sperm motility, while short SHBG alleles were associated with higher sperm concentration, supporting the significance of these genes in spermatogenesis and semen quality.


Journal of Andrology | 2010

Estrogen Receptor α and β Polymorphisms Are Associated With Semen Quality

Leandros Lazaros; Nectaria Xita; Apostolos Kaponis; Konstantinos Zikopoulos; Nicolaos Plachouras; Ioannis Georgiou

The role of estrogen receptor alpha (ER alpha) and estrogen receptor beta (ER beta) gene polymorphisms on semen quality is the aim of our study. One hundred fourteen men were examined in the In Vitro Fertilization Unit of Ioannina Medical School, and it was found that 85 men had normal sperm count and 29 were oligozoospermic. The genotype analysis, on DNA extracted from spermatozoa, revealed that in men with oligozoospermia (sperm concentration <20 x 10(6) spermatozoa/mL), those with ER alpha 397T/C and 397C/C genotypes had higher sperm motility whereas those with 397T/T genotype had lower sperm motility (P = .003). In addition, men with ER alpha 351A/A genotype had lower sperm motility compared with 351A/G and 351 G/G genotypes (P = .013). Furthermore, normal-sperm-count men with ER alpha 397T/T genotype had higher sperm concentration compared with 397T/C and 397C/C genotypes (P = .016), whereas men with ER alpha 351A/A genotype had higher sperm concentration than those with 351A/G and 351G/G genotypes (P = .05). In contrast, no significant associations were found between ER beta (1082G-->A and 1730A-->G) polymorphisms and sperm concentration or motility. In conclusion, ER alpha polymorphisms were found to be associated with sperm motility and concentration. supporting the significance of this gene in spermatogenesis and semen quality.


Reproductive Biomedicine Online | 2003

Reproductive outcome of polycystic ovarian syndrome patients treated with GnRH antagonists and recombinant FSH for IVF/ICSI

Efstratios M. Kolibianakis; Konstantinos Zikopoulos; Carola Albano; Marguerite Camus; Herman Tournaye; André Van Steirteghem; Paul Devroey

The purpose of this prospective study was to assess the reproductive outcome of patients with polycystic ovarian syndrome (PCOS) treated by in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) with recombinant FSH (rFSH) and gonadotrophin releasing hormone (GnRH) antagonists. One hundred and ten patients were evaluated. The starting dose of rFSH was 100 IU in 67 women with body mass index (BMI) </=29 kg/m(2) and 200 IU in 43 women with BMI >29 kg/m(2). GnRH antagonist was started by the detection of a follicle of a 15mm in ultrasound scan. A significantly lower ongoing pregnancy rate per oocyte retrieval (25.6% versus 46.7%, P = 0.04) and a higher occurrence of ovarian hyperstimulation syndrome (16.3% versus 3.0%, P = 0.03) was observed in the group of patients with BMI >29 kg/m(2) as compared with the group of patients with BMI </=29 kg/m(2), respectively. In conclusion, in GnRH antagonist cycles a worse reproductive outcome is expected in PCOS patients with BMI >29 kg/m(2) in whom stimulation is initiated with 200 IU of rFSH as compared with PCOS patients with BMI </=29 kg/m(2) in whom stimulation is initiated with 100 IU of rFSH.


Asian Journal of Andrology | 2011

The association of aromatase (CYP19) gene variants with sperm concentration and motility

Leandros Lazaros; Nectaria Xita; Apostolos Kaponis; Elissavet Hatzi; Nicolaos Plachouras; Nicolaos V. Sofikitis; Konstantinos Zikopoulos; Ioannis Georgiou

The irreversible transformation of androgens into oestrogens is catalysed by cytochrome P450 aromatase. In the present study, we explored the contribution of the (TTTA)(n) polymorphism in the aromatase gene (CYP19) to sperm concentration and motility. Ninety normozoospermic and 60 oligospermic men were examined during infertility examinations. DNA was extracted from spermatozoa, and the CYP19 (TTTA)(n) polymorphism was genotyped by PCR. Genotype analysis revealed six CYP19 (TTTA)(n) alleles with 7-12 repeats. The allelic distribution of the CYP19 (TTTA)(n) polymorphism differed between normozoospermic and oligospermic men (P<0.01). Oligospermic men less frequently had long CYP19 alleles than did normozoospermic men (25 and 37.8%, respectively; P<0.02). The higher frequency of short CYP19 alleles in oligospermic men compared to normozoospermic men (43.3 and 28.3%, respectively; P<0.01) was primarily due to the distribution of the CYP19 (TTTA)(7) allele. The CYP19 (TTTA)(7) allele was associated with lower sperm concentration in normozoospermic men (P<0.01) and in the total study population (P<0.01); it was also associated with lower sperm motility in normozoospermic men (P<0.05) and in the total study population (P<0.01). In conclusion, the CYP19 (TTTA)(7) allele probably impairs aromatase activity, which in turn alters aromatase and oestrogen levels in the testis, leading to decreased sperm concentration and motility. These findings support the significance of cytochrome P450 aromatase in human spermatogenesis and consequently in semen quality.


Reproductive Biology and Endocrinology | 2004

Comparison of Misoprostol and Dinoprostone for elective induction of labour in nulliparous women at full term: A randomized prospective study

E.G. Papanikolaou; Nikos Plachouras; Aikaterini Drougia; Styliani Andronikou; Christina Vlachou; Theodoros Stefos; Evangelos Paraskevaidis; Konstantinos Zikopoulos

BackgroundThe objective of this randomized prospective study was to compare the efficacy of 50 mcg vaginal misoprostol and 3 mg dinoprostone, administered every nine hours for a maximum of three doses, for elective induction of labor in a specific cohort of nulliparous women with an unfavorable cervix and more than 40 weeks of gestation.Material and MethodsOne hundred and sixty-three pregnant women with more than 285 days of gestation were recruited and analyzed. The main outcome measures were time from induction to delivery and incidence of vaginal delivery within 12 and 24 hours. Admission rate to the neonatal intensive care unit within 24 hours post delivery was a secondary outcome.ResultsThe induction-delivery interval was significantly lower in the misoprostol group than in the dinoprostone group (11.9 h vs. 15.5 h, p < 0.001). With misoprostol, more women delivered within 12 hours (57.5% vs. 32.5%, p < 0.01) and 24 hours (98.7% vs. 91.4%, p < 0.05), spontaneous rupture of the membranes occurred more frequently (38.8% vs. 20.5%, p < 0.05), there was less need for oxytocin augmentation (65.8% vs. 81.5%, p < 0.05) and fewer additional doses were required (7.5% vs. 22%, p < 0.05). Although not statistically significant, a lower Caesarean section (CS) rate was observed with misoprostol (7.5% vs. 13.3%, p > 0.05) but with the disadvantage of higher abnormal fetal heart rate (FHR) tracings (22.5% vs. 12%, p > 0.05). From the misoprostol group more neonates were admitted to the intensive neonatal unit, than from the dinoprostone group (13.5% vs. 4.8%, p > 0.05). One woman had an unexplained stillbirth following the administration of one dose of dinoprostone.ConclusionsVaginal misoprostol, compared with dinoprostone in the regimens used, is more effective in elective inductions of labor beyond 40 weeks of gestation. Nevertheless, this is at the expense of more abnormal FHR tracings and more admissions to the neonatal unit, indicating that the faster approach is not necessarily the better approach to childbirth.


Journal of Assisted Reproduction and Genetics | 2011

Assessment of sperm chromatin condensation and ploidy status using flow cytometry correlates to fertilization, embryo quality and pregnancy following in vitro fertilization

Leandros Lazaros; Georgios Vartholomatos; Elissavet Hatzi; Apostolos Kaponis; Georgios Makrydimas; Sophia N. Kalantaridou; Nikolaos Sofikitis; Theodoros I. Stefos; Konstantinos Zikopoulos; Ioannis Georgiou

PurposeSperm flow cytometry (SFC) was used to evaluate the association of sperm chromatin condensation and ploidy with fertilization, embryo development, pregnancy and abortion rates following IVF.MethodsConventional semen analysis was performed in one hundred fifty men, as well as SFC analysis, after acridine orange and propidium iodide staining, for the evaluation of sperm maturity and ploidy respectively. Conventional IVF was performed in all couples.ResultsCouples with low percentages of mature spermatozoa presented with lower fertilization rates (p < 0.005), lower rates of grade A embryos (p < 0.003) and lower pregnancy rates (p < 0.006), compared to couples with high percentages of mature spermatozoa. Couples with low total aneuploidy rates presented with higher fertilization rates (p < 0.007), higher rates of grade A embryos (p < 0.004) and higher pregnancy rates (p < 0.003), compared to couples with high total aneuploidy rates.ConclusionsSperm chromatin condensation and ploidy constitute critical parameters for the evaluation of semen samples before IVF and for the identification of cases in need of ICSI application.

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Paul Devroey

Vrije Universiteit Brussel

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Efstratios M. Kolibianakis

Aristotle University of Thessaloniki

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