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Featured researches published by Jinan Bekir.


Fertility and Sterility | 1999

Value of ovarian stromal blood flow velocity measurement after pituitary suppression in the prediction of ovarian responsiveness and outcome of in vitro fertilization treatment

Lawrence Engmann; Povilas Sladkevicius; Rina Agrawal; Jinan Bekir; Stuart Campbell; Seang Lin Tan

OBJECTIVE To evaluate whether ovarian stromal blood flow velocity after pituitary suppression is predictive of ovarian response and the outcome of IVF treatment in patients with normal basal serum FSH levels and to compare the predictive value of this test with age, early follicular phase serum FSH level, E2 level, and FSH:LH ratio. DESIGN Prospective observational study of women undergoing IVF treatment. SETTING A tertiary referral center for assisted reproduction. PATIENT(S) Eighty-eight women who received the long buserelin acetate treatment protocol. INTERVENTION(S) Transvaginal color and pulsed Doppler measurement of the ovarian stromal peak systolic velocity (PSV) after pituitary suppression and measurement of the basal serum FSH level, E2 level, and FSH:LH ratio. MAIN OUTCOME MEASURE(S) Number of mature oocytes retrieved and pregnancy rate. RESULT(S) Ovarian stromal PSV was the most important single independent predictor of ovarian response in patients with a normal basal serum FSH level, when compared with age, basal FSH level, E2 level, or FSH:LH ratio. Patients in group 2 (PSV > or = 10 cm/s) had a significantly higher median number of mature oocytes retrieved (11 versus 5.5) and a higher clinical pregnancy rate (35.3% versus 11.3%) than patients in group 1 (PSV <10 cm/s), even after controlling for age. CONCLUSION(S) Ovarian stromal blood flow velocity, after pituitary suppression is confirmed, is predictive of ovarian responsiveness and the outcome of IVF treatment.


Obstetrics & Gynecology | 1996

Relationship of ovarian stromal blood flow at the baseline ultrasound scan to subsequent follicular response in an in vitro fertilization program

Jamal Zaidi; Julie Barber; Amma Kyei-Mensah; Jinan Bekir; Stuart Campbell; Seang Lin Tan

Objective To assess whether Doppler indices of intraovarian blood flow are related to the subsequent follicular response in an in vitro fertilization (IVF) program. Methods One hundred five women underwent ultrasonographic assessment of ovarian morphology, transvaginal color Doppler measurement of intraovarian blood flow and immunoassay of serum FSH during the early follicular phase of an IVF cycle. The subsequent follicular response was related to the Doppler data. Results Mean ovarian stromal peak systolic blood flow velocity was significantly correlated with the follicular response (P = .001), even after adjusting for the age of patient, type of ovary (polycystic or normal), total number of human menopausal gonadotropin ampules used, and serum FSH. Mean ovarian stromal pulsatility index was not related to the follicular response. Mean ovarian stromal peak systolic blood flow velocity was significantly lower (P = .007) in the poor-response group. The adjusted odds of a poor response increased significantly by an estimated 22% per cm/second decrease in velocity (P = .02). Conclusion Ovarian stromal blood flow at the baseline ultrasound scan is correlated with subsequent follicular response and may be a new indicator for predicting ovarian responsiveness in an IVF program.


American Journal of Obstetrics and Gynecology | 1994

Cumulative conception and live-birth rates after in vitro fertilization with and without the use of long, short, and ultrashort regimens of the gonadotropin-releasing hormone agonist buserelin

Seang-Lin Tan; Noreen Maconochie; Pat Doyle; Stuart Campbell; Adam Balen; Jinan Bekir; Peter Brinsden; Robert G. Edwards; Howard S. Jacobs

OBJECTIVE Our purpose was to compare cumulative conception and live-birth rates after in vitro fertilization with and without the use of the long, short, and ultrashort regimens of the gonadotropin-releasing hormone agonist buserelin. STUDY DESIGN Life-table analysis of conception and live-birth rates in relation to ovarian stimulation regimen used in 2893 women who had one of five stimulation regimens exclusively throughout all treatment cycles, namely, human menopausal gonadotropin with or without clomiphene citrate; follicle-stimulating hormone with or without clomiphene citrate; and long, short, and ultrashort protocols of buserelin, plus follicle-stimulating hormone or human menopausal gonadotropin; and in an additional 347 women who had been administered both human menopausal gonadotropin and follicle-stimulating hormone with or without clomiphene citrate. RESULTS The cumulative conception rate and cumulative live-birth rate were significantly higher in those women treated exclusively with the long buserelin regimen (59% and 55%, respectively, after three cycles) compared with those who only had human menopausal gonadotropin or follicle-stimulating hormone with or without clomiphene citrate (39% and 29%, respectively, after three cycles) (p = 0.001 and p = 0.0001) or compared with those who had only short or ultrashort buserelin regimens (22% and 17% after two cycles) (p = 0.0001 and p = 0.005). The pregnancy failure rate in patients on the long buserelin regimen was 22.4% (95% confidence interval 14.8% to 30.0%) compared with 33.3% (95% confidence interval 29.6% to 37.0%) in those who had human menopausal gonadotropin or follicle-stimulating hormone with or without clomiphene citrate (p = 0.03). When the probabilities of first conception and first live birth were examined by treatment regimen, after we allowed for the effects of age, cause of infertility, calendar year of treatment, and treatment cycle number (with a multiple logistic regression model), it was found that, relative to human menopausal gonadotropin or follicle-stimulating hormone with or without clomiphene citrate, the odds of conceiving with the long buserelin regimen was 1.63 (95% confidence interval 1.31 to 2.03) (p < 0.001) and the odds of a live birth was 1.97 (95% confidence interval 1.53 to 2.54) (p < 0.001). Similarly, relative to short or ultrashort buserelin the odds of conceiving with long bureselin was 1.88 (95% confidence interval 1.39 to 2.55) (p < 0.001) and the odds of a live birth was 1.79 (95% confidence interval 1.25 to 2.56) (p = 0.001). CONCLUSION Pituitary desensitization with the long protocol of buserelin significantly increases the probabilities of conception and live birth after in vitro fertilization.


British Journal of Obstetrics and Gynaecology | 1999

Cumulative probability of clinical pregnancy and live birth after a multiple cycle IVF package: a more realistic assessment of overall and age-specific success rates?

L. Engmann; Noreen Maconochie; Jinan Bekir; Howard S. Jacobs; Seang Lin Tan

Objective To provide an assessment of pregnancy and live birth probabilities for women presenting for in vitro fertilisation treatment for the first time, when committed in advance to have up to three cycles of treatment in one year.


Journal of Assisted Reproduction and Genetics | 1996

Success of intrauterine insemination using cryopreserved donor sperm is related to the age of the woman and the number of preovulatory follicles

Rudiger Pittrof; Adel Shaker; Nicola Dean; Jinan Bekir; Stuart Campbell; S.L. Tan

AbstractObjective: Our objective was to assess parameters associated with a successful outcome of intrauterine insemination (IUI) using cryopreserved donor sperm. Design: We analyzed 750 consecutive donor IUI cycles undertaken by 363 women in an assisted conception clinic. The main outcome measure was clinical pregnancy. Results: IUI was performed in 94.7% of the 750 IUI treatment cycles commenced and 180 clinical pregnancies occurred. The clinical pregnancy rate per cycle was 26.4%. The rate was significantly related to the patients age (30.5% for age ≤35 years and 18.1% for age >35 years;P<0.006) and whether there was one or more than one preovulatory follicles [20.9, 34.4, and 31.5% for one, two, and three or four follicles with a mean diameter of 14 or more mm at the time of human chorionic gonadotropin (hCG) administration;P=0.006]. Two to four preovulatory follicles were present in 12.6% of the natural cycles, 43.6% of clomiphene citrate or tamoxifen, and 59.9% of gonadotropin stimulated cycles. The difference in the number of preovulatory follicles between stimulated and unstimulated cycles was highly significant (P<0.0001). Pregnancy rates were 29.9% in gonadotropin-stimulated cycles, 23.6% in clomiphene citrate- or tamoxifen-stimulated cycles, and 20.1% in unstimulated cycles. The difference in pregnancy rates between gonadotropin-stimulated and natural cycles was significant (P=0.038). Cycle fecundity rates were not significantly affected by the number of previous treatment cycles, duration of infertility, gravidity and parity of the patient, presence of a spontaneous luteinizing hormone (LH) surge before the administration of hCG, or number of motile sperm in the insemination specimen. Conclusions: Success of IUI using cryopreserved donor sperm is related to the age of the women and whether there is one or more than one preovulatory follicles.


American Journal of Obstetrics and Gynecology | 1999

Progestogen therapy during pituitary desensitization with gonadotropin-releasing hormone agonist prevents functional ovarian cyst formation: A prospective, randomized study

L. Engmann; Noreen Maconochie; Jinan Bekir; S.L. Tan

OBJECTIVES We sought to assess whether the use of norethindrone and gonadotropin-releasing hormone agonist therapy in the early follicular phase reduces the occurrence of functional ovarian cysts and shortens the duration of pituitary desensitization. We also assessed whether the use of norethindrone impairs implantation rates after in vitro fertilization treatment. STUDY DESIGN We performed a prospective, randomized, single-blind study involving 117 patients who were randomized to receive norethindrone 24 hours before gonadotropin-releasing hormone agonist therapy (n = 63, treatment group) or gonadotropin-releasing hormone agonist alone (n = 54, control group) for pituitary desensitization. RESULTS The incidence of functional ovarian cyst formation after 1 week of gonadotropin-releasing hormone agonist therapy was significantly lower in the treatment group compared with the control group. Furthermore, the duration of pituitary suppression was significantly shorter in the treatment group than in the control group. There were no significant differences between the 2 groups in the follicular response and embryo quality. Adjusted for age, the implantation rate (22% vs 9%, P =.02) and clinical pregnancy rate (34% vs 18%, P =.04) were significantly higher in the treatment group than in the control group. CONCLUSION A combination of norethindrone and gonadotropin-releasing hormone agonist therapy is therefore more effective in achieving prompt pituitary suppression and should be considered for routine use during in vitro fertilization cycles.


Fertility and Sterility | 1998

Local Side Effects of Subcutaneous and Intramuscular Urinary Gonadotropins for Ovarian Stimulation in In Vitro Fertilization: A Prospective, Randomized Study

L. Engmann; Adel Shaker; Emma White; Jinan Bekir; Howard S. Jacobs; Seang Lin Tan

OBJECTIVE To compare the incidence and severity of local side effects of urinary-derived gonadotropins administered s.c. and i.m.. DESIGN Prospective randomized study of women undergoing IVF treatment. SETTING Tertiary referral center for assisted reproduction. PATIENT(S) A total of 71 patients were randomized to receive gonadotropins by the s.c. (n = 41) or i.m. (n = 30) route. INTERVENTION(S) One cycle of IVF with gonadotropins administered either s.c. or i.m. for ovarian stimulation. MAIN OUTCOME MEASURE(S) Incidence and severity of local side effects, such as redness, itching, swelling, pain, and bruising. RESULT(S) Pain was the most common side effect, with 55.3% and 70.1% of i.m. and s.c. injections, respectively, resulting in pain. There were no statistically significant differences in the incidence of itching or bruising after i.m. and s.c. injections. Although there was a higher incidence of redness and swelling in the s.c. group compared with the i.m. group, most cases were classified as mild. CONCLUSION(S) There was a significantly higher incidence of some local side effects after s.c. gonadotropin administration but most of these were mild and well tolerated by patients.


Journal of Assisted Reproduction and Genetics | 1996

Outcome of frozen embryo replacement cycles following elective cryopreservation of all embryos in women at risk of developing ovarian hyperstimulation syndrome

Awoniyi O. Awonuga; Nicola Dean; Jamal Zaidi; Rudiger Pittrof; Jinan Bekir; S.L. Tan

AbstractAim: Our aim was to compare the outcome in subsequent frozen embryo replacement cycles in four groups of patients who had elective cryopreservation of all their embryos because they were considered to be at increased risk of developing severe ovarian hyperstimulation syndrome. Design: Sixty-two (91%) of 68 IVF cycles (68 patients) in which elective cryopreservation of all embryos was performed were analyzed. All patients continued on the GnRH agonist, buserelin, after oocyte recovery until the onset of vaginal bleeding. Frozen embryo replacement occurred in a hormone replacement cycle that started either on day 3 of the withdrawal bleed (group I;N=15) or after serum estradiol levels had fallen to <100 pmol/L (group II;N=16). The other patients commenced a frozen embryo replacement cycle several months later in either a hormone replacement (group III;N=15) or a natural (group IV;N=16) cycle. Results: Two patients developed severe ovarian hyperstimulation syndrome. There were no significant differences among the four groups regarding demographic variables, the dose of hMG used, and the clinical outcome. There was a higher but not significantly different clinical pregnancy rate in group I (26.7%), compared to group II (12.5%), group III (13.3%), and group IV (18.8%). Conclusions: Several options exist for the timing and protocol used for frozen embryo replacement in patients who had elective cryopreservation for the prevention of ovarian hyperstimulation syndrome, none of which was found to be clearly superior in this observational report.


Human Reproduction | 1999

The outcome of in-vitro fertilization treatment in women with sonographic evidence of polycystic ovarian morphology

L. Engmann; Noreen Maconochie; Povilas Sladkevicius; Jinan Bekir; Stuart Campbell; Seang Lin Tan


Human Reproduction | 2001

Trends in the incidence of births and multiple births and the factors that determine the probability of multiple birth after IVF treatment

L. Engmann; Noreen Maconochie; Seang Lin Tan; Jinan Bekir

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L. Engmann

University of Connecticut

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Adel Shaker

University of Cambridge

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