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Dive into the research topics where Hal Danzer is active.

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Featured researches published by Hal Danzer.


American Journal of Obstetrics and Gynecology | 1976

Serum human chorionic gonadotropin levels throughout normal pregnancy.

Glenn D. Braunstein; Joan Rasor; Donald Adler; Hal Danzer; Maclyn E. Wade

Human chorionic gonadotropin (hCG) levels were measured in the sera of 443 pregnant women by the beta-hCG radioimmunoassay in order to determine if the third-trimester secondary peak in hCG levels observed by less specific immunoassays was due to cross-reacting substances. hCG was detected as early as six days after presumed conception and peaked between 56 and 68 days, with a nadir at 18 weeks. No secondary rise in hCG levels was demonstrated, indicating that the nonspecific hCG immunoassays give spuriously high values for hCG during the last trimester of pregnancy.


Fertility and Sterility | 2008

Accuracy of FISH analysis in predicting chromosomal status in patients undergoing preimplantation genetic diagnosis

Catherine Marin DeUgarte; M. Li; Mark Surrey; Hal Danzer; David E. Hill; Alan H. DeCherney

OBJECTIVEnThe purpose of this study was to determine the positive predictive value (PPV) and negative predictive value (NPV) of FISH analysis and to determine which chromosomal abnormalities are most frequently confirmed.nnnDESIGNnProspective observational.nnnSETTINGnIVF laboratory.nnnPATIENT(S)nTwo hundred forty-one embryos were analyzed from 98 patients.nnnINTERVENTION(S)nFISH reanalysis.nnnMAIN OUTCOME MEASURE(S)nEmbryos that would have been discarded in patients undergoing preimplantation genetic diagnosis (PGD) were fixed and FISH reanalysis was performed. Results of reanalysis were compared with the day 3 diagnosis while PPV and NPV were calculated.nnnRESULT(S)nAmong the 241 embryos, 198 embryos were abnormal and 43 were normal by day 3 FISH analysis. The PPV was 83% and the NPV was 81%. PPV was also determined for specific categories of aneuploidy, and certain abnormalities such as monosomies, trisomies, tetrasomies, and polyploidies were frequently confirmed on reanalysis (PPV >80%), whereas Turner syndrome diagnosis was not (PPV = 17%).nnnCONCLUSION(S)nFISH analysis offers a PPV of 83% and NPV of 81% when evaluating a single blastomere in conjunction with PGD. FISH errors and mosaicism are primarily responsible for the errors associated with FISH analysis in PGD.


American Journal of Obstetrics and Gynecology | 1981

A randomized prospective study of the use-effectiveness of two methods of natural family planning☆

Maclyn E. Wade; Phyllis McCarthy; Glenn D. Braunstein; James R. Abernathy; C.M. Suchindran; George S. Harris; Hal Danzer; William A. Uricchio

The final results of a prospective comparative study of two methods of natural family planning indicate a significant difference in the 12 month net cumulative pregnancy rates between the ovulation and symptothermal methods. These differences are on the order of two to one in favor of the symptothermal method. Pearl pregnancy rates confirm similar differentials between the two methods. Dropout rates for both methods were high. Lack of interest or dissatisfaction with the method was the major reason for dropout training while pregnancy or desire for pregnancy were the major reasons for dropout during the formal phase of the study.


American Journal of Obstetrics and Gynecology | 1979

A randomized prospective study of the use-effectiveness of two methods of natural family planning: an interim report.

Maclyn F. Wade; Phyllis McCarthy; James R. Abernathy; George S. Harris; Hal Danzer; William A. Uricchio

Data accumulated to date from the Los Angeles study indicate that the total termination rate for 12 months from the beginning of the training period and from formal entry into the study was high for the ovulation method (OM), and symptothermal method (STM). Voluntary withdrawal was the highest single reason for termination in both methods. The 12 month voluntary withdrawal rate, measured from formal entry into the study, was significantly higher for OM users. Pregnancy rates measured from both the beginning of training and formal entry into the study were significantly higher for OM users than for STM users. Complete analysis of the data collected during the study is currently in progress. It is anticipated that some of the causes for the differences in pregnancy rates and withdrawal rates between the two methods can be identified.


Fertility and Sterility | 1991

Micromanipulation in a center for reproductive medicine

D.L. Hill; Donald Adler; Cappy Miles Rothman; Mark Surrey; Hal Danzer; Stanley Friedman

Several variations of micromanipulation of the female gamete (zona drilling, zona cracking, ooplasmic sperm injection, partial zona dissection) have been applied recently to human IVF to overcome severe male factor. Of the first 16 cycles attempted using partial zona dissection, one pregnancy resulted leading to a normal term delivery. Careful removal of the coronal cells, as well as stepwise removal of sucrose postpartial zona dissection, will facilitate this procedure and greatly reduce potential damage to the oocyte by pH, mechanical, or thermal injury. Micromanipulation has become a routine service offered in our program in cases where the likelihood of a poor IVF outcome is either known or suspected, and also serves as a replacement for simple reinsemination in cases of failed fertilization.


Journal of Assisted Reproduction and Genetics | 2002

Is Gender Selection an Appropriate Use of Medical Resources

D.L. Hill; Mark Surrey; Hal Danzer

Gender selection by PGD is an appropriate use of medical resources. Children borne through PGD for gender determination would be welcome and would come into a couples life at a planned, opportune time. If the practice were made more available through insurance coverage, the size and makeup of families could become a matter of choice rather than chance for couples favoring this approach.


Journal of Assisted Reproduction and Genetics | 2013

The clinical ramifications of polycystic ovarian morphology in oocyte donors

M. Cho; G. Ambartsumyan; Hal Danzer; K. Brennan; Mark Surrey

ObjectiveTo determine the relationship between Polycystic Ovary (PCO) morphology and In Vitro Fertilization (IVF) outcome in oocyte donation cycles.DesignCross sectional studySettingPrivate IVF clinicPatients164 consecutive ovum donors and their recipients were reviewed, 149 were included in the study where 113 patients had normal ovarian morphology and 36 patients had PCO morphology.InterventionsAll donors underwent ovarian stimulation in conjunction with GnRH agonist or antagonist in standard fashion.Main Outcome MeasuresBaseline donor characteristics were recorded, as well as details of IVF stimulation and embryo data. Recipient data on pregnancy and miscarriage were also collected.ResultsPatients with PCO ovaries had significantly higher peak estradiol levels and required less gonadotropins during IVF stimulation. In addition, the baseline characteristics between donor groups did not differ except for ovarian morphology. The number of oocytes retrieved and indicators of embryo quality did not differ between the two groups, and there was no significant difference between pregnancy and miscarriage rates in the recipients.ConclusionsOocyte donors with PCO morphology have equivalent pregnancy rates and do not need to be excluded as potential donors.


Taiwanese Journal of Obstetrics & Gynecology | 2014

Chromosome abnormalities in embryos derived from microsurgical epididymal sperm aspiration and testicular sperm extraction

Shao-Ping Fred Weng; Mark Surrey; Hal Danzer; D.L. Hill; Pau-Chung Chen; Tsung-Chieh Jackson Wu

OBJECTIVEnTo evaluate the patterns of chromosome abnormalities in embryos derived from intracytoplasmic sperm injection (ICSI) in microsurgical epididymal sperm aspiration (MESA) or testicular sperm extraction (TESE) in comparison to embryos that are derived from naturally ejaculated (EJAC) patients.nnnMATERIALS AND METHODSnMale partners with azoospermia who required MESA or TESE for ICSI were studied for chromosomal abnormalities. The ICSI patients with EJAC sperm served as the control group. Preimplantation genetic diagnosis (PGD) was performed by fluorescence in situ hybridization (FISH). Chromosome abnormalities were categorized as polyploidy, haploidy, aneuploidy, and complex abnormality (which involves more than two chromosomes). Fertilization, embryo development, and patterns of chromosome abnormalities were accessed and evaluated.nnnRESULTSnThere was no difference between the MESA, TESE, and EJAC patient groups in the rates of fertilization and pregnancy and the percentages of euploid embryos. In all three groups, less than one-half of the embryos for each group were normal (41xa0±xa031%, 48xa0±xa038%, and 48xa0±xa031% in MESA, TESA, and EJAC, respectively). Complex chromosomal abnormality was significantly more frequent in the MESA group than in the EJAC group (48.3% vs. 26.5%, respectively; pxa0<xa00.001). Furthermore, the overall pattern of chromosomal aneuploidy was similar among all three studied groups.nnnCONCLUSIONnWe suggest that MESA and TESE, followed by ICSI and PGD, appear to be acceptable approaches for treating men with severe spermatogenesis impairment.


Obstetrics & Gynecology | 2015

Characteristics of Donor Oocyte In Vitro Fertilization Cycles Resulting in Pregnancy: Optimum Number of Oocytes and Embryos [351]

Tracy Nicole Hadnott; Anupama S.Q. Kathiresan; David E. Hill; Mark Surrey; Hal Danzer; J. Barritt

INTRODUCTION: The objective of this study was to compare characteristics of donor in vitro fertilization (IVF) cycles that did and did not result in pregnancy. Additionally, we sought to identify the optimal number of retrieved oocytes and good-quality embryos needed to maximize pregnancy rates in fresh donor IVF cycles. METHODS: We conducted a retrospective analysis of donor oocyte cycles at a single large private fertility clinic between 2010 and 2013. Parametric and nonparametric statistical analyses were used to compare cycles that did and did not result in pregnancy. Receiver operating characteristic curves were used to evaluate the optimal number of retrieved oocytes and good-quality embryos predictive of pregnancy. RESULTS: An overall clinical pregnancy rate of 58.5% was found among the 318 fresh donor cycles analyzed. There was no difference in donor age, number of total or mature oocytes retrieved, fertilization rate, or number of embryos transferred or frozen between the two groups. There was a trend toward higher number of good-quality embryos in the pregnant group (6.3 compared with 7.2, P=.06). The optimal number of retrieved oocytes and good-quality embryos predictive of pregnancy was 18 oocytes and 5.5 embryos, respectively (area under the curve [confidence interval] 0.55 [0.49–0.61] and 0.57 [0.50–0.63]). CONCLUSION AND IMPLICATION: Donor egg banks should consider avoiding cycles that result in extremely high numbers of retrieved oocytes because this does not improve pregnancy outcomes. Larger studies are needed to validate our findings and to demonstrate the optimal use of a limited quantity of viable, pregnancy-producing oocytes.


Fertility and Sterility | 2013

Significant improvement in pregnancy rates following frozen embryo transfers when combined with microarray-comparative genomic hybridization (aCGH)

David E. Hill; Mark Surrey; Hal Danzer; S. Ghadir; W. Chang; J. Barritt

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Mark Surrey

Cedars-Sinai Medical Center

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D.L. Hill

University of California

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M. Surrey

University of California

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S. Ghadir

University of California

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J. Barritt

Icahn School of Medicine at Mount Sinai

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W. Chang

Cedars-Sinai Medical Center

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Shao-Ping Weng

National Taiwan University

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M. Li

University of California

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Donald Adler

University of California

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