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Featured researches published by Zeev Blumenfeld.


Fertility and Sterility | 2002

Thrombophilia is common in women with idiopathic pregnancy loss and is associated with late pregnancy wastage

Galit Sarig; Johnny S. Younis; Ron Hoffman; Naomi Lanir; Zeev Blumenfeld; Benjamin Brenner

OBJECTIVE To describe the characteristics of thrombophilia in women with idiopathic pregnancy loss. DESIGN Prospective observational study. SETTING Tertiary referral center in a teaching academic hospital. PATIENT(S) One hundred forty-five patients with repeated pregnancy loss and 145 matched controls. INTERVENTION(S) Prospective assessment of thrombophilia in patients and controls. MAIN OUTCOME MEASURE(S) Prevalence of activated protein C (APC) resistance, protein C, protein S, and antithrombin III deficiencies, antiphospholipid antibodies, factor V Leiden, factor II G20210A, and MTHFR C677T mutations. RESULT(S) At least one thrombophilic defect was found in 66% of study group patients compared with 28% in control group patients. Combined thrombophilic defects were documented in 21% of women with pregnancy loss compared with 5.5% of control patients. Late pregnancy wastage occurred more frequently in women with thrombophilia compared with women without thrombophilia (160/429 [37%] vs. 39/162 [24%], respectively). APC resistance was documented in 39% of women with pregnancy loss compared with 3% of the control patients. APC resistance without factor V Leiden mutation was documented in 18% of women with pregnancy loss compared with none of the controls. While factor V Leiden mutation was more common in women with pregnancy loss (25% vs. 7.6%), factor II G20210A and homozygosity for MTHFR C677T contributed to pregnancy loss only in the presence of other thrombophilia. CONCLUSION(S) Thrombophilia was found in the majority (66%) of women with idiopathic pregnancy loss. APC resistance with or without factor V Leiden mutation is the most common thrombophilic defect, and combined thrombophilia is a frequent finding in women with pregnancy loss. Thrombophilia is associated with increased frequency of late pregnancy wastage.


Human Reproduction Update | 2008

GnRH-analogues and oral contraceptives for fertility preservation in women during chemotherapy

Zeev Blumenfeld; Michael von Wolff

BACKGROUND For preserving fertility in women during chemotherapy, the character of invasive techniques, such as ovarian cryopreservation and other techniques, await further experience. Meanwhile, non-invasive techniques have attempted to minimize the gonadotoxic effect of chemotherapy, by using gonadotrophin-releasing hormone-analogues (GnRH-a) or oral contraceptives (OC). METHODS We performed a computerized MEDLINE search to identify articles published on fertility preservation using GnRH-a or OCs. RESULTS Nine human-controlled studies reported the use of GnRH-a and four reported the use of OCs in parallel to chemotherapy. All nine studies analysing the effect of GnRH-a found lower rates of premature ovarian failure (POF) in patients receiving GnRH-a compared with the controls. Summarizing the studies resulted in 11.1% incidence of POF in patients who received GnRH-a compared with 55.5% incidence in the controls. Evidence using the fertility preserving effect of OC is limited. Two studies showed lower POF rates in OC-treated patients. The summarized data revealed a POF rate of 13.2% in patients who received OCs compared with that of 29.8% in the controls. CONCLUSIONS The published clinical studies provide evidence, but do not prove statistically, that GnRH-a co-treatment reduces gonadotoxicity. Owing to the retrospective and non-randomized nature of most of the studies, definite conclusions concerning the reduction of POF by GnRH-a can still not be unequivocally drawn. As GnRH-a and OC have no serious side effects and as GnRH-a can even reduce chemotherapy-induced complications, such as severe menometrorrhagia, GnRH-a are considered by many clinicians as a clinically useful co-treatment in chemotherapy. The published clinical studies on OC also suggest a possible effect on the reduction of POF under certain conditions.


British Journal of Haematology | 1997

Activated protein C resistance can be associated with recurrent fetal loss

Benjamin Brenner; Hanna Mandel; Naomi Lanir; Johnny S. Younis; Haim Rothbart; Gonen Ohel; Zeev Blumenfeld

As thrombosis of placental vessels may result in recurrent fetal loss, we analysed 39 consecutive women with recurrent fetal loss of unknown cause for activated protein C resistance. Factor V Leiden (FVL) mutation (19 cases) or APC resistance without FVL (nine cases) were found among these 39 women.  Evaluation of 128 pregnancies in 19 patients with factor V Leiden mutation and 56 gestations in nine women with acquired APC resistance, revealed over 50% first‐trimester abortions and 17% late abortions. Intra‐uterine fetal death occurred in nine out of 19 FVL patients (47%). Only 34 of 184 gestations (18%) in hereditary or acquired APC‐resistance women resulted in a live birth, with 11 of the 34 (32%) being premature deliveries. These data suggest that, in some patients with recurrent fetal loss, hereditary and acquired APC resistance are potential causes of vascular placental insufficiency.


Journal of the American College of Cardiology | 1991

Cardiac involvement in patients with primary antiphospholipid syndrome

Benjamin Brenner; Zeev Blumenfeld; Walter Markiewicz; Shimon A. Reisner

To evaluate cardiac involvement in primary antiphospholipid syndrome, two-dimensional and Doppler echocardiographic studies were performed in 34 consecutive patients with this syndrome. All patients had an increased level of serum anticardiolipin antibodies with no evidence of malignancy or systemic lupus erythematosus. The clinical manifestations of primary antiphospholipid syndrome were arterial thrombosis in 14 patients, venous thrombosis in 6 and recurrent fetal loss in 14. Valvular lesions were observed on two-dimensional echocardiography in 11 patients (32%) (9 women and 2 men), aged 24 to 57 years (mean +/- 1 SD 36 +/- 10). Abnormal echocardiographic findings were observed in 9 (64%) of 14 patients with arterial thrombosis versus 1 (17%) of 6 patients with venous thrombosis and 1 (7%) of 14 patients with recurrent fetal loss. The most common echocardiographic abnormality was mitral leaflet thickening, found in five patients; this was associated with mitral regurgitation in three and with combined mild mitral stenosis and regurgitation in one patient. Localized subvalvular mitral thickening was observed in one patient and calcification of the anulus in another. Aortic valve thickening was observed in two patients, one of whom also had a moderate degree of aortic regurgitation. Vegetation-like lesions on the mitral or aortic valve were found in two patients. It is concluded that valvular lesions are commonly found in primary antiphospholipid syndrome, particularly when the syndrome is manifested by peripheral arterial thrombosis. The location and appearance of valvular lesions in this syndrome are heterogeneous. Most patients have no clinically significant valvular disease. Two-dimensional and Doppler echocardiographic studies are often informative in these patients.


American Journal of Obstetrics and Gynecology | 1989

First-trimester and early second-trimester diagnosis of nuchal cystic hygroma by transvaginal sonography: Diverse prognosis of the septated from the nonseptated lesion

Moshe Bronshtein; Shraga Rottem; N. Yoffe; Zeev Blumenfeld

Fetal cystic hygroma is a congenital malformation of the lymphatic system appearing as a single or multiloculated fluid-filled cavity, most often in the nuchal region. The malformation is believed to arise from failure of the lymphatic system to communicate with the venous nuchal system. Sometimes the lesion progresses to fetal hydrops, causing fetal death. To further delineate the cause and natural history of this disorder, we have prospectively studied eight cases of cystic hygroma of the neck, detected at gestational ages of 9 to 15 weeks by transvaginal sonography. Three of the eight fetuses survived (37.5%) and were normal at birth. Either hydrops fetalis or intrauterine fetal death occurred in the other five fetuses. In one of these five, therapeutic abortion was induced because of trisomy 21. In another fetus of these five, trisomy 18 was diagnosed by amniocentesis. This pregnancy ended in intrauterine fetal death. The ultrasonic evaluation of the cystic hygromas revealed that those that were reabsorbed in the three ultimately normal viable fetuses were nonseptated cysts, whereas all the four cystic hygromas ending in fetal death or associated with aneuploidy were septated, multilocular hygromas. In another fetus with nonseptated hygroma, nonimmune hydrops developed, which resulted in premature delivery and early neonatal death.


Fertility and Sterility | 1999

Thrombophilia-associated pregnancy wastage

Zeev Blumenfeld; Benjamin Brenner

OBJECTIVE To critically review the literature regarding inherited thrombophilia and recurrent fetal loss. DESIGN English-language literature review. PATIENT(S) Women who experienced repeated pregnancy wastage. INTERVENTION(S) Aspirin, glucocorticoids, heparin, and IV immunoglobulin for the prevention of miscarriage. MAIN OUTCOME MEASURE(S) Live birth, miscarriage, preeclampsia, and pregnancy loss. RESULT(S) Recurrent fetal loss and other placental vascular pathologies of pregnancy have long been associated with antiphospholipid syndrome, an acquired autoimmune thrombophilic state. The number of known heritable thrombophilic disorders has grown rapidly in recent years with the identification of activated protein C resistance, factor V Leiden mutation, and hyperhomocysteinemia as major causes of thrombosis. Data accumulated over the past 2 years suggest that heritable thrombophilia is associated with an increased risk of fetal loss and preeclampsia. The present review discusses potential pathogenetic mechanisms for this association and evaluates reported therapeutic regimens for the prevention of fetal loss in women with thrombophilia. CONCLUSION(S) Placental thrombosis may be the final common pathophysiologic pathway in most women with habitual abortions and repeated pregnancy wastage. Prophylactic antithrombotic therapy is indicated in women with heritable thrombophilia and antiphospholipid syndrome and probably is more effective than the previously used modalities of prednisone, aspirin, and IV immunoglobulin.


Annals of Medicine | 1997

Prevention of Gonadal Damage during Cytotoxic Therapy

Zeev Blumenfeld; Nissim Haim

Infertility represents one of the main remote sequelae of cytotoxic chemotherapy given for various malignant diseases. The impairment of gonadal function after cytotoxic chemotherapy is more frequent in the male than in the female. Because dividing cells are more sensitive to the cytotoxic effects of alkylating agents than are cells at rest, it has been hypothesized that inhibition of the pituitary-gonadal axis by gonadotropin-releasing hormone (GnRH) agonists would render the germinal epithelium less susceptible to the cytotoxic effects of chemotherapy. This hypothesis has not been thoroughly clinically tested until recently, although several investigators have demonstrated that GnRH-agonistic analogues (GnRH-a) inhibit chemotherapy-induced ovarian follicular depletion in the rat and Rhesus monkeys. Based on this rationale, we have undertaken a prospective evaluation to determine whether GnRH-a administration during combination chemotherapy for Hodgkins and non-Hodgkins lymphoma could prevent posttreatment ovarian damage in women by inducing a temporary prepubertal hormonal milieu. While over 93% of the surviving patients in the GnRH-a and chemotherapy group resumed spontaneous ovulation and menses, less than 40% of the women in the control group of chemotherapy without the GnRH-a cotreatment resumed normal ovarian cyclic activity. More than 60% of the women experienced premature ovarian failure (POF) in the chemotherapy alone group. Our preliminary results suggest that GnRH-a cotreatment protects against POF during cytotoxic chemotherapy. The GnRH-a and chemotherapy cotreatment may be also suggested for young women treated by cyclophosphamide pulse therapy or other gonadotoxic treatments for systemic lupus erythematosus, organ transplantation and other autoimmune diseases. The technology of cryopreservation of human ova for future fertility in these patients awaits clinical validation and substantiation. This review discusses possibilities to prevent gonadal damage induced by cytotoxic therapy and presents the clinical data currently available.


Fertility and Sterility | 1981

Factors affecting sperm motility. vii. sperm viability as affected by change of ph and osmolarity of semen and urine specimens

Amnon Makler; Rami David; Zeev Blumenfeld; Ori S. Better

The effects of pH and osmolarity of semen and urine specimens on motility and velocity of human spermatozoa were studied objectively with the aid of the multiple exposure photography (MEP) method. The pH of fresh ejaculates ranged from 7.2 to 8.2 and specimens were slightly hyperosmotic ranging between 300 to 380 mOsm/kg. Gradually changing the pH and osmolarity to either side of normal values led to progressive loss of sperm motility. However, sperm velocity was slightly increased by mild alkalinization and hyperosmolarity. Spermatozoa that became immobilized by acidification regained their motility shortly after pH was restored to normal values. In the majority of instances spermatozoa lost their motility when mixed with fresh urine specimens. Neutralization of urinary pH could not protect them from this effect unless urine osmolarity was also isotonically adjusted. It is suggested that patients with retrograde ejaculation should adequately increase their fluid intake before recovery of sperm from their bladder for artificial insemination.


Fertility and Sterility | 1993

Premature ovarian failure—the prognostic application of autoimmunity on conception after ovulation induction

Zeev Blumenfeld; Sar’el Halachmi; B. Alik Peretz; Zehava Shmuel; Dov Golan; Amnon Makler; Joseph M. Brandes

OBJECTIVE To assess whether the presence of autoimmune activity in patients with premature ovarian failure (POF) can predict the response to ovulation induction and conception. DESIGN Assessment of autoimmune activity in patients with POF, correlating the response to ovulation induction with this autoreactivity. SETTING Tertiary care academic center. PATIENTS Forty women with POF, 15 of them treated by ovulation induction because of infertility. INTERVENTIONS All patients were tested for the presence of autoimmune activity, antibodies against various tissues, and 15 of them were treated with combinations of hMG/hCG, glucocorticosteroids as immunosuppressant, and some of them also with a long-acting GnRH agonist. Those patients not interested in infertility were put on hormone replacement therapy (HRT). MAIN OUTCOME MEASURES Serum E2 and P were measured during ovulation induction as well as follicular diameter monitoring by transvaginal sonography. Achievement of gestations and their outcome were monitored in the group in which ovulation induction was accomplished. RESULTS Antibodies against thyroglobulin, nuclear antigens, heart, tissue gluten, or increased levels of immunoglobulin (Ig)M, or decreased levels of complement C3 and C4 were significantly different in the patients with POF than in the control population. Autoreactivity of at least one class of the tested antibodies was found in 31 of 40 patients (77%). In 15 patients with autoimmune activity who have undergone ovulation induction using hMG/hCG, 14 pregnancies were achieved in 8 patients. Two of the pregnancies were spontaneous, and 12 were generated by hMG/hCG and fluocortolone, with or without pretreatment with GnRH-a. Twelve healthy babies were generated by 10 gestations, 3 ended in spontaneous abortions (23%), and 1 is ongoing. All the nonspontaneous pregnancies were achieved in the first three cycles of ovulation induction. CONCLUSIONS Patients with POF and autoimmune activity, suggesting an autoimmune etiology to the ovarian failure, may respond to ovulation induction and have a conception rate of approximately 40% in three cycles. Those who do not conceive in three treatment cycles have a very low probability to conceive; therefore, further attempts of ovulation induction should be discouraged. However, some patients may spontaneously conceive in association with HRT.


The Cleft Palate-Craniofacial Journal | 1999

The Early Prenatal Diagnosis of Cleft Lip and the Decision–Making Process

Zeev Blumenfeld; Israel Blumenfeld; Moshe Bronshtein

In 1996, Bronshtein et al. published an article entitled “Early prenatal diagnosis of cleft lip and its potential impact on the number of babies with cleft lip” in the British Journal of Oral and M...

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Moshe Bronshtein

Technion – Israel Institute of Technology

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Joseph M. Brandes

Technion – Israel Institute of Technology

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Etan Z. Zimmer

Technion – Israel Institute of Technology

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Eldad J. Dann

Rambam Health Care Campus

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N. Yoffe

Technion – Israel Institute of Technology

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Judith Stoller

Technion – Israel Institute of Technology

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Ron Epelbaum

Rappaport Faculty of Medicine

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Galit Sarig

Technion – Israel Institute of Technology

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