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Dive into the research topics where Rafael Levi is active.

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Featured researches published by Rafael Levi.


Journal of Obstetrics and Gynaecology Research | 2004

Premature luteinization defined as progesterone estradiol ratio >1 on hCG administration day seems to adversely affect clinical outcome in long gonadotropin-releasing hormone agonist cycles

Hasan Tayfun Ozcakir; Rafael Levi; Erol Tavmergen; Ege Nazan Tavmergen Göker

Aim:  To examine the effect of premature luteinization on the outcomes in long gonadotropin‐releasing hormone agonist cycles.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2002

Comparison of the ICSI outcome of ejaculated sperm with normal, abnormal parameters and testicular sperm.

Ege Nazan Tavmergen Göker; Fatih Sendag; Rafael Levi; Handan Sendag; Erol Tavmergen

OBJECTIVE(S) To compare fertilization rates, quality of embryos, pregnancy rates (PRs) and outcome of pregnancies in intracytoplasmic sperm injection (ICSI) using sperm from ejaculates of normal and abnormal semen and testicular sperm of non-obstructive azoospermia. STUDY DESIGN Four hundred fifty-four patients who underwent 454 ICSI cycles were evaluated retrospectively. Patients were divided into three groups according to the quality and source of sperm. Patients in group 1 underwent 133 cycles of ICSI using ejaculated normal semen, group 2 underwent 235 cycles using ejaculated abnormal semen, and group 3 underwent 86 cycles using testicular sperm. RESULTS The parameters were compared among the groups with respect to cycles induced by long (n = 160) and short (n = 294) protocol. In group 3, the fertilization and PRs were significantly lower than in all other groups (51.3 and 10.6% in the long protocol cycles, 53.3 and 5.1% in the short protocol cycles, respectively). There was no significant difference in the outcome of pregnancies in respect to abortion rates between different groups. CONCLUSION(S) The fertilizing ability of sperm in ICSI is highest with ejaculated sperm and lowest with sperm extracted by testicular biopsy. Also, the clinical PRs are significantly lower in ICSI with sperm from testicular biopsy. However, the outcomes of pregnancies are not affected by using surgically retrieved sperm from ejaculated semen.


Journal of Obstetrics and Gynaecology Research | 2001

Bilateral Jugular Venous Thromboembolism and Pulmonary Emboli in a Patient with Severe Ovarian Hyperstimulation Syndrome

Erol Tavmergen; Hasan Tayfun Özçakir; Rafael Levi; Şaban Adakan; Murat Ulukus; Mustafa Cosan Terek

We report here a case of severe ovarian hyperstimulation syndrome with massive ascites in a 25‐year‐old woman with a history of primary infertility after an IVF‐ET cycle. At the 9th gestational week she presented with neck pain and dyspnea and duplex Doppler sonographic examination of the neck veins revealed bilateral jugular venous thrombosis. Despite prompt administration of low‐molecular weight heparin, pulmonary emboli developed a few days later.


Archives of Gynecology and Obstetrics | 2002

Relationship of follicle number, serum estradiol level, and other factors to clinical pregnancy rate in gonadotropin-induced intrauterine insemination cycles

Hasan Tayfun Özçakir; E.N. Tavmergen Goker; Mustafa Cosan Terek; Saban Adakan; Murat Ulukus; Rafael Levi; Erol Tavmergen

Abstract  Objective:To determine the characteristics associated with clinical pregnancy rate after gonadotropin-induced intrauterine insemination cycles in patients without male or tubal factor infertility. Materials and methods:One hundred and eighty patients undergoing controlled ovarian hyperstimulation followed by intrauterine insemination were included in the study retrospectively. The patients’ files were retrospectively evaluated with respect to age, number of follicles, endometrial thickness and serum hormone levels at baseline and at the day of human chorionic gonadotropin (hCG) administration. The patients with male or unilateral tubal factor infertility were excluded from the study. Results:The serum estradiol level at the day of hCG administration was not correlated with the clinical pregnancy rate (r=–0.05, p=0.481). The number of follicles was not correlated with the clinical pregnancy rate (r=–0.09, p=0.209). There was no significant difference between the clinically pregnants (n=32) and not pregnants (n=148) regarding the mean age, baseline serum levels of luteinizing hormone (LH) and estradiol, serum estradiol and LH levels at the day of hCG administration and endometrial thickness (p>0.05). Although not statistically significant, a pregnancy rate of 14.2% with less than 3 follicles ≥18 mm is present compared to a pregnancy rate of 27.5% with at least 3 follicles ≥18 mm and 24% with ≥4 follicles ≥18 mm. Conclusion: The clinical pregnancy rate does not seem to be affected with the number of follicles present at the time of intrauterine insemination or the serum estradiol level at the day of hCG administration in a controlled ovarian hyperstimulation cycle in non-andrologic and non-peritubal factor infertility; however, there is a clear trend towards higher pregnancy rates with higher number of follicles.


Archives of Gynecology and Obstetrics | 2002

Comparison of short and long ovulation induction protocols used in ART applications according to the ovarian response and outcome of pregnancy.

Erol Tavmergen; E.N. Tavmergen Goker; Fatih Sendag; H. Sendag; Rafael Levi

Abstract This retrospective study was designed to determine whether there is any difference between short and long protocol ovulation induction with Gonadotropin Releasing Hormone agonist (GnRHa) and gonadotropins used in Assisted Reproductive Technology (ART) applications according to the number of retrieved oocytes, oocyte maturity, fertilization rates, embryo quality and the outcome of pregnancies. 240 cycles consisting of in vitro fertilization (IVF) cycles without andrologic factor and intracytoplasmic sperm injection (ICSI) cycles were evaluated. 112 cycles which were induced by short protocol GnRHa and Follicle Stimulating Hormone (FSH) + Human Menopausal Gonadotropin (HMG) combinations and 128 cycles which were induced by long protocol GnRHa and FSH + HMG combinations were compared according to the number of retrieved oocytes, cancellation rate of cycles, oocyte maturity, fertilization rates, embryo quality and pregnancy rates. The cancellation rate for short protocol cycles were found to be significantly higher than those with long protocol. The number of retrieved oocytes, mature oocytes and fertilized oocytes were also found significantly lower. The quality of embryos did not show any significant difference between these groups. The clinical pregnancy rates were evidently found to be high in the long protocol cycles. As a conclusion we have found that while the number of retrieved oocytes, mature oocytes, fertilized oocytes and clinical pregnancy rates were increasing, the cancellation rate of cycles were decreasing significantly in ART cycles induced by long protocol.


Journal of Obstetrics and Gynaecology Research | 2001

Unilateral Ectopic Twin Pregnancy Following an IVF Cycle

Ege Nazan Tavmergen Göker; Erol Tavmergen; H. Tayfun Özçakir; Rafael Levi; Şaban Adakan

We report here a 37‐year‐old woman who underwent ovulation induction and in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment because of infertility who developed vaginal bleeding at the 6th week of gestation. Abdominal ultrasonography was insufficient to distinguish the intrauterine gestational sac. Subsequently, vaginal doppler ultrasonography detected two separate unilateral twin ectopic pregnancies with cardiac activity in both fetuses, which were operated on pelviscopically.


Archives of Gynecology and Obstetrics | 2002

Controlled ovarian hyperstimulation and intrauterine insemination for infertility associated with endometriosis: a retrospective analysis

E.N. Tavmergen Goker; Hasan Tayfun Özçakir; Mustafa Cosan Terek; Rafael Levi; Saban Adakan; Erol Tavmergen

Abstract Objective To evaluate the efficacy of controlled ovarian hyperstimulation and intrauterine insemination for infertility associated with endometriosis. Material and methods A retrospective analysis of 260 patients with the only diagnosis of endometriosis, or male factor, or tubal factor, or unexplained infertility were performed: a total of 56 patients with different stages of endometriosis, a control group consisting of 38 patients with male factor infertility, a group of 26 patients with tubal factor infertility and a group of 140 patients with others (unexplained infertility, ovulation disorders, cervical factor). Pregnancy rate, hormone levels, endometrial thickness and number of follicles were analyzed. Results Clinical pregnancy rates per patient were similar between endometriosis, male factor, tubal factor, and others including unexplained infertility, ovulation disorders and cervical factor groups (10.7%, 5.4%, 11.5%, 17.9%, respectively; p>0.05). Clinical pregnancy rates per patient were not effected between the 2 subgroups of endometriosis as minimal to mild and moderate to severe [5.1% (2/39) versus 23.5% (4/17), p=0.19]. Conclusion Endometriosis did not affect the clinical pregnancy rate per patient compared to the other infertility factors. Endometriosis of various stages have no effect on the success of controlled ovarian hyperstimulation combined with intrauterine insemination.


Journal of Obstetrics and Gynaecology Research | 2003

The outcomes of assisted reproductive technology cycles in patients with one or two ovaries

Rafael Levi; Hasan Tayfun Özçakir; Erkan Alatas; Ege Nazan Tavmergen Göker; Erol Tavmergen

Aim: To provide a comparison between the follicular response to ovulation induction, and the pregnancy rate of women with a single or two ovaries, undergoing assisted reproductive technology.


Journal of Obstetrics and Gynaecology Research | 2003

Effect of ovarian cysts detected on the beginning day of ovulation induction to the success rates in ART cycles

Rafael Levi; Hasan Tayfun Özçakir; Saban Adakan; Ege Nazan Tavmergen Göker; Erol Tavmergen

Aim:  In the present study, we examined the outcome of assisted reproductive technology cycles in patients with or without baseline ovarian cysts following gonadotrophin‐releasing hormone analogs administration.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2003

Complete down-regulation is not mandatory for good assisted reproductive treatment cycle outcomes

Rafael Levi; L. Kupelioglu; H.T. Özçakýr; Z. Cebi; Saban Adakan; Ege Nazan Tavmergen Göker; Erol Tavmergen

OBJECTIVE To determine the implications and predictive value of estradiol concentrations following pituitary down-regulation with gonadotrophin releasing hormone agonists in women undergoing controlled ovarian hyperstimulation for assisted reproductive technology. STUDY DESIGN A total of 277 patients undergoing ovarian hyperstimulation for intracytoplasmic sperm injection (ICSI) were enrolled into the study and the patients were divided into four groups according to estradiol levels on the initial day of stimulation of which group-A consisted of the patients who had < or =25 pg/ml (n=90), group-B with levels between 26 and 50 pg/ml (n=104), group-C with levels between 51 and 75 pg/ml (n=67) and group-D with levels > or =76-90 pg/ml (n=16) and the results were compared. The primary outcome measures included ovarian response and the clinical pregnancy rates. RESULTS The clinical pregnancy rates in groups-A, B, C and D were 33.3% (30/90), 26.0% (27/104), 35.8% (24/67), and 25.0% (4/16), respectively, and there was no statistically significant difference (P=0.482). The mean number of oocytes retrieved in groups were (9.7+/-5.8, 10.3+/-6.5, 11.0+/-6.8, and 12.1+/-6.6), respectively (P=0.453) and the fertilization rates in groups-A, B, C and D were found to be similar (75, 80, 73 and 79%, respectively; P=0.658). CONCLUSION Complete and deep desensitization obviously seems not to be mandatory for successful stimulation in assisted reproductive technology cycles.

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