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Biomedical subjects

A Dorfmann

Publications and source records attributed to A Dorfmann.

At least 19 recordsLinked to original sources
PubMed2001

Pregnancy rates in sequential in vitro fertilization cycles by oocyte donors(1).

OBJECTIVE: To evaluate the clinical outcome of in vitro fertilization (IVF) treatment cycles from individual oocyte donors who underwent multiple sequential donations. METHODS: We reviewed clinical outcome data from sequential anonymous oocyte donation cycles using donors who underwent multiple IVF stimulations. Donors were grouped by the interval between cycles and the cycle number (rank). The primary outcome measure was delivery rate by individual donor per retrieval from the combined derivative fresh and frozen embryo transfers. RESULTS: Duration and amount of gonadotropin therapy and the fertilization rates did not correlate significantly with the interval between cycles or cycle rank. Cumulative delivered pregnancy rates for cycles 1-6 were 51.5%, 54.6%, 50.5%, 51.5%, 51.1%, and 57.6%, respectively. Delivered pregnancy rates did not vary by interval between cycles. CONCLUSION: Young healthy presumed or proven fertile women can reliably donate oocytes for at least six cycles with the expectation of consistently high pregnancy rates.

Adolescent↗
PubMed1999

Preimplantation genetic diagnosis for spinal muscular atrophy type I.

OBJECTIVE: Couples with children who have spinal muscular atrophy type I (SMA) face a 25% risk of having affected offspring with spontaneous conception. Preimplantation genetic testing (PGT) is possible for the deletions in the survival motor neuron (SMN) gene that have been identified in 98% of SMA type I cases. PGT would provide new reproductive options for families at risk for SMA. METHODS: Three couples with previously affected children confirmed by DNA testing each underwent in vitro fertilization (IVF) and PGT of the resulting embryos. One or two blastomeres were biopsied from each embryo and analyzed for deletions in exons 7 and 8 of the SMN gene. RESULTS: Nine embryos were predicted to be unaffected, three to be affected, and one embryo could not be interpreted. One of three patients receiving transfer of unaffected embryos became pregnant with twins. CONCLUSIONS: Preimplantation genetic testing provides a means for couples at risk for spinal muscular atrophy type I to reduce their chance of initiating an affected pregnancy.

Adult↗
PubMed1997

Comparison of ultrasonographic findings in spontaneous abortions with normal and abnormal karyotypes.

To determine whether ultrasonographic findings can predict the karyotype of spontaneous abortions, 137 pregnancies (54 spontaneous, 83 assisted ovulatory cycles) that subsequently aborted and had chromosome analysis performed on the products of conception were studied ultrasonographically. Transvaginal ultrasound was performed using an Acuson 128XP/10 with 7.5 MHz probe. The numbers of empty gestational sacs, small and normal for gestational size, embryonic poles and embryos with documented cardiac activity were calculated. The frequency of each of these findings in pregnancies with normal and abnormal karyotypes was compared. Of the 137 spontaneous abortions, 51 had normal chromosome analyses and 86 had abnormal karyotypes (68 aneuploidies and 18 polyploidies). Ultrasonographic findings in the 51 karyotypically normal pregnancies included 16 (31%) with empty gestational sacs, and 35 (69%) with embryonic poles, of which 24 (69%) were at least 1 week smaller than expected for gestational age and 11 (31%) were the expected size. Embryonic cardiac activity was documented in 22 (63%) of the 35 embryonic poles. Amongst 86 pregnancies with abnormal karyotypes, similar frequencies of ultrasound findings were found: 23 (27%) with empty gestational sacs, 42 (67%) with embryonic poles smaller than expected for gestational age, and 50 (79%) embryos lost after documentation of embryonic cardiac activity. No differences in the frequency of ultrasonographic findings of empty gestational sacs, small embryonic pole and embryonic cardiac activity were observed between karyotypically normal and abnormal spontaneous abortions. Ultrasonographic findings cannot predict the karyotype of spontaneous abortions.

Abortion, Spontaneous↗
PubMed1996

Comparisons of pregnancy loss patterns after intracytoplasmic sperm injection and other assisted reproductive technologies.

OBJECTIVE: To compare outcome of pregnancies after intracytoplasmic sperm injection (ICSI) with those of other assisted reproductive technologies. DESIGN: Pregnancy outcomes after ICSI were followed prospectively and compared with pregnancy outcomes after IVF with fresh and frozen ETs and donor oocyte cycles. SETTING: A private tertiary referral center for genetics and infertility in Fairfax, Virginia. PATIENTS: One hundred thirty-six couples achieving pregnancy after undergoing ICSI, 71 after IVF, 35 donor oocyte recipients, and 19 after transfer of frozen-thawed embryos. INTERVENTIONS: In vitro fertilization and/or ET for all couples. Dilatation and curettage to obtain products of conception for chromosome analysis in 28 women experiencing spontaneous abortion. MAIN OUTCOME MEASURES: Pregnancy outcomes were classified as preclinical loss, clinical loss, and ongoing pregnancy. RESULTS: The mean frequency of preclinical pregnancy loss was 26% after ICSI, 28% after IVF, 3% after ET using donor oocytes, and 11% after frozen ET. The rate of clinical loss after ICSI (21%) was compared with IVF (18%), donor oocyte cycles (11%), and frozen ETs (21%). CONCLUSIONS: Intracytoplasmic sperm injection is not associated with an increase in pregnancy losses, clinical or preclinical, compared with conventional IVF.

Abortion, Spontaneous↗
PubMed1995

Intracytoplasmic sperm injection facilitates fertilization even in the most severe forms of male infertility: pregnancy outcome correlates with maternal age and number of eggs available.

OBJECTIVE: To evaluate, in a prospective study, the fertilization and pregnancy rates after intracytoplasmic sperm injection (ICSI) in infertile couples with severe male infertility. DESIGN: Intracytoplasmic sperm injection was performed in 229 consecutive IVF cycles on 190 couples with rigorously defined severe male infertility or proven failure of fertilization in prior IVF cycles. Neither male nor female partners were chosen from a waiting list or on any other selective basis, including age, prior or anticipated ovarian response, or oocyte number or quality. There were no upper age limits, in no instance was donor sperm used for ICSI, and cycle cancellation rate was minimal. SETTING: Private genetics and fertility center in Fairfax, Virginia. MAIN OUTCOME MEASURES: Fertilization, transfer, and pregnancy rates were measured in ICSI-treated couples, and comparisons were made regarding both female age and strictly defined semen categories. RESULTS: Two hundred six cycles (90%) resulted in ETs, with initiation of 52 pregnancies (25% per transfer, 23% per cycle). Thirty-eight of 52 (18% per transfer) were clinical pregnancies with established gestational sacs or were ongoing or delivered. Pregnancies were achieved even in older women but were more readily established in younger women producing larger numbers of metaphase II oocytes. The severity of semen abnormalities had some small effect on fertilization rate, but only actual necrospermia was associated with markedly decreased frequency of embryo formation. Pregnancy per transfer was similar across groups. In some cases, pregnancy was initiated with fewer than 100 viable sperm in the ejaculate. CONCLUSIONS: Intracytoplasmic sperm injection is a very powerful new treatment for severe male infertility. Paradoxically, egg number and probably egg quality are now the main determinants of success in treating male infertility.

Adult↗
PubMed1994

Mental retardation and Ullrich-Turner syndrome in cases with 45,X/46X,+mar: additional support for the loss of the X-inactivation center hypothesis.

Four cases having mosaicism for a small marker or ring [45,X/46,X,+mar or 45,X/46,X,+r] chromosome were ascertained following cytogenetic studies requested because of minor anomalies (cases 1, 3, and 4) and/or short stature (cases 2 and 4). While all 4 cases had traits typical of Ullrich-Turner syndrome (UTS), cases 1, 3, and 4 had manifestations not usually present in UTS, including unusual facial appearance, mental retardation/developmental delay (MR/DD) (cases 3 and 4), and syndactylies (case 1). The facial appearances of cases 1 and 3 were similar yet distinct from that of case 4. Using fluorescence in situ hybridization (FISH), each of the markers in these 4 cases was identified as having been derived from an X chromosome. The level of mosaicism for the mar/r(X) cell line in these cases varied from 70% (case 1) to 16% (case 4) but was not apparently correlated with the presence of MR/DD. Replication studies demonstrated a probable early replication pattern for the mar/r(X) in cases 1, 3, and 4, while the marker in case 2 was apparently late replicating. To date, 41 individuals having mosaicism for a small mar/r(X) chromosome have been described. Interestingly, most of the 14 individuals having a presumedly active mar/r(X) demonstrated clinical findings atypical of UTS, including abnormal facial changes (11) and MR/DD (13). MR was noted most frequently in those cases having at least 50% mosaicism for the marker or ring. In contrast, atypical UTS facial appearance or MR/DD was not noted in 14 of the 16 cases with UTS who carried a probable late replicating marker or ring. In conclusion, although the phenotype of 45,X/46,X,mar/r(X) individuals appears to be influenced by the genetic content and degree of mosaicism for the mar/r(X), the most significant factor associated with MR/DD appears to be the activity status of the mar/r(X) chromosome. Thus, our 4 cases provide further support for the hypothesis that a lack of inactivation of a small mar/r(X) chromosome may be a factor leading to the MR and other phenotypic abnormalities seen in this subset of individuals having atypical UTS.

Child↗
PubMed1994

Acrosome reaction inducibility predicts fertilization success at in-vitro fertilization.

We prospectively studied the ability of acrosome reaction (AR) inducibility to predict fertilization success in a group of 232 infertile patients presenting sequentially for in-vitro fertilization (IVF). The median percentage of eggs fertilized for the overall patient population was 25% (interquartile range 5-58%), with one to 29 oocytes available for insemination (median, five oocytes). The median percentage of eggs fertilized at IVF increased as the percentage of spermatozoa able to undergo AR became greater: spermatozoa with a failed AR (< or = 5%) fertilized only 12% of eggs, while spermatozoa with AR values > 9% fertilized 50% of eggs. The assay had a specificity of 0.75, a sensitivity of 0.55 and an odds ratio of 2.9; thus, AR-positive patients are 2.9 times more likely to achieve fertilization than patients with a failed AR. Receiver operator characteristic (ROC) curves were constructed for AR, sperm concentration and percentage of normal forms in semen. All three parameters proved to be potentially useful in predicting the occurrence of fertilization, although AR and morphology appeared to be better than sperm concentration by ROC analysis. Patients were divided into four clearly defined subgroups according to their traditional semen characteristics, including morphology. The median percentage of eggs fertilized decreased as traditional semen characteristics deteriorated, from a median of 46% for patients with excellent sperm concentration, motility and morphology, to a median of 29% for patients with suboptimal semen quality and a median of 0% for patients with severely impaired semen.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrosome↗
PubMed1993

Gender preselection in humans? Flow cytometric separation of X and Y spermatozoa for the prevention of X-linked diseases.

Human X- and Y-chromosome-bearing spermatozoa were separated based on their DNA content, using modified flow cytometric cell sorting technology. The resulting separation purity of the X-bearing from Y-bearing spermatozoa was evaluated using in-situ hybridization with alpha satellite DNA probes for the X- and Y-chromosomes. In the putative X-enriched-sorted populations, an average of 82% of the spermatozoa showed a hybridization signal with the X probe. Similarly, in the Y-sorted population 75% gave a signal with the Y probe. Sorted X- and Y-bearing spermatozoa were found to maintain their viability for several hours after sorting. These results demonstrate that the human sperm sex ratio can be significantly shifted to favour the selection of female-producing (X) spermatozoa or male-producing (Y) spermatozoa when spermatozoa are flow cytometrically sorted on the basis of DNA content. We propose that flow cytometrically sorted human spermatozoa, used in conjunction with in-vitro fertilization or intra-oviductal insemination, could be used by families who are at risk for X-linked diseases to preferentially produce female offspring. Sorted spermatozoa could also be used to pre-select for male offspring if that were medically indicated.

Cell Separation↗
PubMed1991

Confirmation of CVS mosaicism in term placentae and high frequency of intrauterine growth retardation association with confined placental mosaicism.

About 2 per cent of specimens from chorionic villus sampling (CVS) analysed either on direct preparation of cytotrophoblast cells or after culture of mesenchymal stroma reveal confined placental mosaicism (CPM), most commonly involving chromosomal trisomy. A significantly higher rate of prenatal loss (22 per cent) as well as the presence of intrauterine growth retardation (IUGR) has been reported among pregnancies with CPM. To evaluate more precisely the effect of these aneuploid cell lines confined to the placenta on intrauterine fetal growth and fetal survival, we have studied 34 term placentae from pregnancies with CPM diagnosed on CVS and confirmed identical mosaicism in 17 of these placentae. There was a direct correlation between a high number of aneuploid cells present at CVS and a high likelihood of their detection in term placenta. Also, the proportion of aneuploid cells in the mosaic term placentae correlated with that observed in CVS specimens. Among 17 gestations with confirmed CPM at delivery, there were six cases of IUGR identified, five in liveborns and one associated with intrauterine death.

Amnion↗
PubMed1990

Small increases in circulating luteinizing hormone (LH) concentrations shortly before human chorionic gonadotropin (hCG) are associated with reduced in vitro fertilization (IVF) pregnancy rate.

The effects of slight elevations in serum LH just before hCG administration on IVF cycle outcome were studied in 219 women undergoing retrieval. One hundred seven patients were stimulated using human menopausal gonadotropin (hMG), and 112 received clomiphene citrate and hMG. Serum LH, estradiol (E2), and progesterone concentrations were measured before and during controlled ovarian stimulation. Retrospectively the women were subdivided into three groups based on serum LH before hCG: Group I, less than 50% LH rise from baseline (BL) value (mean of day 2 and day 7); Group II, LH rise greater than or equal to 50% but less than 2 x BL; and, Group III, LH rise greater than or equal to 2 x BL. The fertilization and cleavage rates were similar in all groups. However, a greater than or equal to 50% rise in serum LH before hCG was associated with a significantly reduced IVF pregnancy rate.

Chorionic Gonadotropin↗
PubMed1988

Chorionic villus sampling: experience with an initial 940 cases.

Of over 1000 patients referred to the Genetics & IVF Institute for chorionic villus sampling, 10% had an abnormal gestational sac at the time of initial presentation. Villus sampling could not be performed in 0.6% of cases, usually because of fibroids. Chorioamnionitis, probably related to the procedure, occurred in two patients (0.2%). The total fetal loss was 2.4%, which is not significantly different from the background fetal loss rate reported in normal pregnancies after eight weeks of gestation. The procedure-related loss was estimated as approximately 0.6%. The cytogenetic analysis routinely used was "direct" trophoblast karyotyping. There were no false-negative diagnoses. Trophoblastic mosaicism was observed in 1.3% of samples. Amniocentesis was performed in 3.5% of cases because of chorionic villus sampling failure, chorionic mosaicism, or elevated maternal serum alpha-fetoprotein (MSAFP) concentrations. Chorionic villus sampling was not associated with falsely elevated MSAFP levels at 15-18 weeks' gestation. Chorionic villus sampling has proved a safe and accurate prenatal diagnostic method associated with relatively low risk when performed by an experienced team, although additional amniocentesis will be necessary in a small percentage of pregnancies.

Adult↗
PubMed1976

[The problem of Caesarean section (author's transl)].

The Caesarean sections at the Universitäts-Frauenklinik Innsbruck from January 1st, 1969 to December 31st, 1974 have been surveyed. Related to the total number of 12 579 deliveries 627 Caesarean sections have been performed. Two 3-year-intervals have been compared: 1969-1971 (group I) without and 1972-1974 (group II) with modern practices of prenatal supervision. There was a high significant increase of the section rate in group II (5,8% versus 4,1% which has been related to the increasing number of mainly fetal indications. The maternal morbidity didn't rise with the increasing section rate. A significant decrease in total infant mortality rate and mortality rate at vaginal deliveries has been found with the increasing incidence of Caesarean sections; whereas the number of depressed infants (Apgar score less than 7) was increased in group II. The reasons therefore have been discussed. The rise of the number of Caesarean sections in group II performed because of breech presentation (14,2% versus 6,2%) was correspondent with a statistically significant decrease in the mortality rate from 11,7 to 4,1%. A Caesarean section rate between 7% and 10% seems to be the limit at least in our hospital--the total infant mortality rate cannot be reduced by further increasing the section frequency: the infant mortality rate possibly could be lowered by a better and more wide spread prenatal care especially by taking more care for prematurity and by intensifying the perinatal period.

Apgar Score↗
PubMed1975

[Significance of various oxytocin challenge tests in monitoring pregnant women at risk (author's transl)].

Three different oxytocin challenge tests were used for the anssessment of placentar function in pregnant women at risk: For the oxytocin test after Ray et al. Oxytocin was given in continuity with rising doses. In the two other tests Oxytocin was given intermittently with identical doses. The test described by Ray et al. Proved useful for predicting respiratory insufficiency of the placenta. The two other intermittent tests are, according to our investigations, less suitable as tests of placentar function because their significance is limited or non-existent. The continuous oxytocin challenge test takes more time (one hour on average). Essential for exact interpretation are a careful technique and surveillance of the patient throughout the test by trained personel. In our opinion the indications for the continous oxytocin challenge test are pregnancies at risk, where antepartum cardniotocography shows suspect or hard-to-interprete results (e.g. non-classifiables decelerations, loss of fluctuation, absence of Braxton-Hicks contractions) or when other monitoring techniques indicate placentar insufficiency (e.g. low oestriol excretion). The test is not suitable in placenta previaprevia, threatened premature birth and premature ruptur of the membranes. In contrast to other authors we cannot decide with certainly whether patients with a positive oxytocin challenge test should in every case be treated with Caesarean section [9]. This decision will depend not only on the result of the test but on the assessment of all parameters, mainly on the clinical picture. In any case delivery of patients with positive oxytocin challenge tests will have to be carried out under strict technical and biochemical supervision.

Cesarean Section↗