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Dive into the research topics where Josef Blankstein is active.

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Featured researches published by Josef Blankstein.


Fertility and Sterility | 1987

Ovarian hyperstimulation syndrome: prediction by number and size of preovulatory ovarian follicles *

Josef Blankstein; Josef Shalev; Tova Saadon; Ehud Kukia; Jaron Rabinovici; Clara Pariente; B. Lunenfeld; David M. Serr; Shlomo Mashiach

Monitoring of human menopausal gonadotropin (hMG) treatment for induction of ovulation according to either preovulatory estrogen levels or the presence of a dominant ovarian follicle was found insufficient to prevent ovarian hyperstimulation syndrome (OHS). In 65 infertile patients treated with hMG and human chorionic gonadotropin (hCG), a possible correlation between the number and size of all ovarian follicles on the day of assumed ovulation and the occurrence of OHS was evaluated in order to assess the value of ultrasonography in predicting OHS. It was found that patients with OHS had significantly more follicles at the time of hCG than patients without OHS. Mild OHS was characterized by the presence of eight to nine follicles, 68.7% of which were of intermediate size (9 to 15 mm). In moderate to severe OHS 95% of the preovulatory follicles were less than 16 mm, most of them (54.7%) less than 9 mm in diameter. It can be concluded that a specific preovulatory follicular configuration characterizes mild and severe hyperstimulation. This is important information before hCG administration and emphasizes the value of ovarian ultrasonography in predicting OHS.


Fertility and Sterility | 1987

Estrogen receptor binding material in blood of patients after clomiphene citrate administration: determination by a radioreceptor assay.

Avraham Geier; B. Lunenfeld; Clara Pariente; Shlomo Kotev-Emeth; Ariela Shadmi; Ehud Kokia; Josef Blankstein

The aim of the current study was to assess whether clomiphene citrate (CC) and/or active metabolites are present at presumed time of ovulation, nidation, or steroid-sensitive organogenesis, in serum of patients receiving CC for induction of ovulation. A radioreceptor assay, based on competitive replacement of 3H-estradiol on the rat uterus estrogen receptor, by ligands present in serum of patients after CC administration, was developed. Ligands reached maximal concentration 4 to 5 hours after a single dose of CC was administered, and declined with a half-life of 4.5 to 10 hours. In patients receiving CC on day 5 to day 9 in the cycle, ligands are still present on day 14 in the cycle and in some patients on day 22 of the cycle, but no ligands were detected 60 days after CC treatment.


British Journal of Obstetrics and Gynaecology | 1987

Rescue of menotrophin cycles prone to develop ovarian hyperstimulation

Jaron Rabinovici; Ori Kushnir; Josef Shalev; Mordechai Goldenberg; Josef Blankstein

Summary. In an attempt to prevent the loss of‘overstimulated cycles’ associated with human menopausal gonadotrophin (hMG)‐induced ovulation, oestradiol levels and ovarian follicular state were monitored in 12 women with‘overstimulated cycles’ after withholding hMG for several days. Human chorionic gonadotrophin (hCG) was administered when oestradiol levels were 1700 pg/ml and the leading follicles between 17 and 22 mm in diameter. During the withholding period follicular growth continued in all patients, while oestradiol levels declined in all but three. These three patients conceived. Ovulation was observed in six additional women. Ovarian hyperstimulation did not occur in any of the 12 patients. We conclude that a rescue of‘overstimulated cycles’ is sometimes possible. Conception seems to depend on a continuing rise of E2 levels and early detection of‘overstimulation’.


Gynecological Endocrinology | 1987

Abolishment of the positive feedback mechanism: A criterion for temporary medical hypophysectomy by LH-RH agonist

Ariela Shadmi; B. Lunenfeld; C. Bahan; Ehud Kokia; Clara Pariente; Josef Blankstein

The hypothalamic pituitary axis was studied in patients with an abnormal pattern of gonadotropin release during chronic treatment with LH-RH agonist. Two patients had PCOD and the third demonstrated the early luteinization phenomenon. Following a well-defined gonadotropin rise with initiation of LH-RH treatment, no further response was noted. Stabilization of the LH:FSH ratio in PCOD patients was noted after 4 weeks of treatment. Administration of both native LH-RH (100 micrograms) and intravenous pulsatile LH-RH did not evoke any rise in LH. In addition to the above LH-RH challenges, the positive feedback was examined by administration of estradiol benzoate (EB). The study demonstrated that, although the pituitary did not respond to any LH-RH challenge, it may still respond by a rise in LH following EB administration. Both functions of the hypothalamic pituitary axis should be examined in order to determine the state of medical hypophysectomy.


Acta Obstetricia et Gynecologica Scandinavica | 1988

The effect of clomiphene citrate and tamoxifen on the cervical mucus.

Ron Tepper; B. Lunenfeld; J. Shalev; Jardena Ovadia; Josef Blankstein

The anti‐estrogenic effect of clomiphene citrate (CC) and tamoxifen (TMX) on cervical mucus was evaluated in a prospective crossover study. Ten women underwent randomized alternate cyclical treatment with either 100 mg CC, 40 mg TMX daily, or with placebo. The effect of CC, TMX and placebo on serum estradiol (E2), cervical mucus secretion and on the development of ovarian follicles was evaluated. Compared with placebo, treatment with CC and TMX significantly increased the number of mature ovarian follicles on the day of assumed ovulation (p <0.05), elevated E, secretion (p <0.05) and decreased cervical score (p <0.05). It can be concluded that anti‐estrogenic agents reduced the secretion of cervical mucus. However, in most cases, the excessive E, production due to multiple follicular growth overcomes the anti‐estrogenic effect.


Fertility and Sterility | 1989

Pituitary and ovarian suppression rate after high dosage of gonadotropin-releasing hormone agonist

David Bider; Zion Ben-Rafael; Josef Shalev; Mordechai Goldenberg; Shlomo Mashiach; Josef Blankstein

Ten infertile menstruating women were treated with daily injections of gonadotropin-releasing hormone agonist (GnRH-a). The GnRH-a (Buserelin; Hoe 766, Hoechst-AG, Frankfurt/Main, West Germany) was administered subcutaneously (SC) from day 9 of the cycle for 6 days, and intranasally (1.2 mg) for 15 days. Before treatment, all ten women had a normal response to Buserelin challenge test and the GnRH test, and seven of the ten responded to estradiol (E 2 ) benzoate test (2 mg intramuscularly). The SC administration ofBuserelin (1.5 mg) for 6 days resulted in suppression of pituitary activity. Continuous treatment with Buserelin (1.2 mg for 3 weeks) was effective as demonstrated by decreasing serum E 2 levels to below 20 pg/ml, and in the absence of ovarian follicles in ultrasonographic scanning. Three days after cessation of Buserelin treatment, the pituitary again responded to the GnRH test. Thus, the authors concluded that the administration of Buserelin in very high doses can induce medical hypophysectomy within 6 days, but over 3 weeks of suppression therapy are required to abolish ovarian findings. Desensitization of the pituitary was reversible within 3 days of cessation of the treatment.


Fertility and Sterility | 1989

The role of gonadotropins in the etiology of ectopic pregnancy.

Gabriel Oelsner; Yehezkeal Menashe; Ilan Tur-Kaspa; Zion Ben-Rafael; Josef Blankstein; David M. Serr; Shlomo Mashiach

Our study indicates that the high rate of EP in MAP(+) patients, treated with hMG/hCG, is due to the fact that it is a selected group of infertile patients with probable additional underlying tubal disease. Absence of EP in MAP(-) patients indirectly support the theory that a mechanical factor is at work. It is, therefore, our opinion, that the cause of ectopic pregnancy lies in the patient and not in the drug (hMG/hCG).


Fertility and Sterility | 1989

Comparison of five clomiphene citrate dosage regimens: follicular recruitment and distribution in the human ovary

Josef Shalev; Mordechai Goldenberg; Ehud Kukia; Dan Lewinthal; Ron Tepper; Shlomo Mashiach; Josef Blankstein

One hundred fifty-six women with cycle disorders presenting as absence or infrequency of ovulation and with luteal phase deficiency (group II, according to the World Health Organization classification) received clomiphene citrate (CC) for ovulation induction. The administered dosage ranged from 50 to 250 mg/d. The follicular development in terms of numbers of small (less than 8 mm), intermediate (9 to 15 mm), and large (greater than 15 mm) follicles and their distribution in either one or both ovaries on the day of assumed ovulation was related to the dosage of CC. A statistically significant increase was found in the total number of follicles in relation to the dosage of CC (P less than 0.003). In view of the development of the mature follicles, the gradual increase in CC daily dosage was thought to be associated with additional mature follicles before ovulation. However, this increased follicular recruitment was not regarded as statistically significant. Treatment with low doses of CC resulted in follicular development in only one ovary, whereas increased follicular recruitment after high CC dosage was found in association with follicular development in both ovaries.


Fertility and Sterility | 1986

Male to female ratio after gonadotropin-induced ovulation

Zion Ben-Rafael; Andre Matalon; Josef Blankstein; David M. Serr; B. Lunenfeld; Shlomo Mashiach

Two hundred fifty-six children were born in 195 births from 176 women that conceived after human menopausal gonadotropin/human chorionic gonadotropin (hMG/hCG)-induced ovulation. The secondary sex ratio was 50% male to 50% female births, which is not statistically different from the Israeli or Occidental population. The same trend was observed for single births and for twins. Thus, the data presented do not support the reports of increased numbers of female infants in those conceived after induction of ovulation. Factors that are expected to have been shown to affect sex ratio: maternal age at delivery, total number of ampules of hMG/hCG administered in the conceptional cycle, urinary estrogen levels on the day of hCG injection, degree of ovarian hyperstimulation syndrome, and time of insemination in relation to the basal body temperature rise were found to be insignificant. Thus, the hypothesis that a local hormonal environment (gonadotropin or estrogen levels) during hMG/hCG treatment possibly affects sex selection was not confirmed.


Contraception | 1987

The influence of different copper wires on human sperm penetration into bovine cervical mucus, in vitro

Zeev Shoham; Arie Lidor; Emanuel Megory; B. Lunenfeld; Josef Blankstein; R. Weissenberg

The influence of four different copper-containing intrauterine devices (IUD) (Nova-T, Multiload, Fincoid 250 and copper-T 250) on the penetration of human sperm into bovine cervical mucus were assessed. Pooled samples of predetermined sperm concentration were suspended in Earls medium in which a copper IUD was previously incubated for periods between one hour to fourteen days. The mean copper concentration was determined for each of the medium containing IUD and was found to be between 284 +/- 93 micrograms/100 ml to 392 +/- 138 micrograms/100ml. While there was no adverse effect on sperm motility by the copper-containing medium, there was a significant reduction in the number of sperm penetrated into the bovine cervical mucus as compared to the penetration of sperm suspended in pure Earls medium. It therefore seems that the influence of copper on sperm penetration might be by an effect on the environment or spermatozoal migration rather than by direct effect of copper on sperm motility.

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David M. Serr

Hebrew University of Jerusalem

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