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G Tews

Publications and source records attributed to G Tews.

At least 37 records · Page 2Linked to original sources
PubMed2001

A prospective study on oocyte survival rate after ICSI: influence of injection technique and morphological features.

PURPOSE: To determine the influence of technical pitfalls and oocyte morphology on survival rate and cleavage behavior after ICSI. METHODS: A total of 2210 injection procedures was examined for morphological and technical deviations. Survival rate and cleavage behavior were evaluated. RESULTS: In 77.8% of all cases ICSI was unsuspicous. Out of 491 deviations from optimal injection deep penetration of the oocyte and abundant presence of cumulus cells showed significant correlation with degeneration rate (p < 0.001). Morphological anomalies associated with the periphery of the oocyte were rather related to degeneration than cytoplasmic anomalies (p < 0.001). Early embryonic development was not impaired by technical or morphological parameters. CONCLUSIONS: To conclude, these prospective data may be of prognostic value in regard of the number of embryos available for transfer and may help to improve treatment outcome.

Adult↗
PubMed2001

Acute puerperal inversion of the uterus--treatment by a new abdominal uterus preserving approach.

OBJECTIVE: Inversion of the uterus is still a rare (1, 2) but serious and life-threatening obstetric complication. It is said to be complete when the fundus uteri protrudes through the cervix and into the vagina. Within minutes a state of shock is reached due to pulling forces on the peritoneum as well as blood loss. METHODS: The vagina was entered by a longitudinal incision (3 m) below the contraction ring. Through this opening it was possible to advance two fingers (second and third finger of the left hand) into the vagina above the invaginated corpus uteri. The invaginated cavum uteri was loaded on these two fingers and, exerting counterpressure with the right hand, the inside was turned out. CONCLUSION: The present operative method guarantees easy reposition of the uterus in cases of failed vaginal manual repositioning. Furthermore, the cavum uteri remains intact and hysterectomy can be avoided.

Adult↗
PubMed2001

Laser assisted immobilization of spermatozoa prior to intracytoplasmic sperm injection in humans.

BACKGROUND: The conventional method of immobilization of spermatozoa prior to intracytoplasmic sperm injection (ICSI) is mechanical breakage of the tail by pressing it against the bottom of the injection dish. METHODS: This prospective self-controlled study was set up to evaluate the potential of a non-contact 1.48 microm wavelength diode laser in terms of immobilization. In addition, the fertilization rate and further development potential of such zygotes were investigated. The patients included in our study (n = 60) had oestradiol concentrations >2000 pg/ml, and thus a relatively high number of MII oocytes could be expected. Approximately half the oocytes were injected with laser treated spermatozoa (n = 262, study group) and the other half with mechanically immobilized spermatozoa (n = 252, control group). RESULTS: No significant differences between the two groups in terms of fertilization rate, early cleavage or blastocyst formation were observed. However, time required for identification, aspiration and injection of a potential spermatozoa was significantly shorter in the laser immobilized sperm group (P < 0.001). CONCLUSIONS: The application of a non-contact diode laser for sperm immobilization prior to ICSI is a potentially useful alternative to the conventional mechanical approach.

Adult↗
PubMed2000

Role of three-dimensional ultrasonographic measurement of endometrium volume as a predictor of pregnancy outcome in an IVF-ET program: a preliminary study.

OBJECTIVE: To evaluate the role of three-dimensional (3D) ultrasonographic measurement of the endometrium in predicting pregnancy in an IVF-ET program. DESIGN: Prospective study. SETTING: Center for assisted reproductive techniques. PATIENT(S): 65 women undergoing controlled ovarian hyperstimulation for IVF. INTERVENTION(S): Ultrasonographic examination on the day of hCG administration. MAIN OUTCOME MEASURE(S): Endometrial volume, endometrial thickness, and pregnancy rate. RESULT(S): The mean (+/-SD) endometrium volume (4.16 +/- 1.97 mL), endometrium thickness (11 +/- 2 mm), and estradiol level (1686.82 +/- 1057.10 pg/mL) in 21 pregnant women on the day of hCG administration did not differ statistically differ from the respective values in 44 nonpregnant women (4.53 +/- 1.79 mL; 11 +/- 2 mm, 1883.56 +/- 1147.21 pg/mL). Receiver-operating characteristic curves showed that the area under curve (AUC) was 0.57 for endometrial volume and 0.48 for endometrial thickness. Using a cut-off value of 2.5 mL for endometrial volume to predict pregnancy, results of the Fisher exact test were statistically significant. No significant cut-off value was found for endometrial thickness. CONCLUSION(S): Endometrial volume and thickness on the day of hCG administration did not predict occurrence of pregnancy. A minimum volume of 2.5 mL appeared to favor pregnancy. The predictive value of 3D ultrasonographic measurement of endometrial volume and thickness was better than that of 2D measurement.

Austria↗
PubMed2000

Prognostic value of first polar body morphology on fertilization rate and embryo quality in intracytoplasmic sperm injection.

The association between oocyte morphology and subsequent fertilization rate and embryo quality in intracytoplasmic sperm injection (ICSI) is subject to considerable controversy. This retrospective study was carried out to investigate a possible prognostic value of first polar body morphology with regard to fertilization rate and embryo quality. A total of 70 consecutive ICSI cases was included in this study. The results showed that classification based on first polar body morphology revealed a significant correlation with fertilization rate (P < 0.025) and embryo quality (P < 0.001). Cytoplasmic criteria showed no correlation in this respect. Present data indicate that ICSI of oocytes with intact well-shaped first polar bodies yields higher fertilization rates and higher quality embryos.

Adult↗
PubMed2000

Three-dimensional endometrial volume estimation as a predictor of pituitary down-regulation in an IVF-embryo transfer programme.

To examine the role of three-dimensional (3D) volume estimation in predicting pituitary down-regulation in an IVF-embryo transfer programme, 46 women were treated with buserelin acetate for down-regulation prior to and concomitantly with ovarian stimulation. Receiver operating characteristic (ROC) curve analysis was used for statistics. The area under the curve (AUC) provides a measure to show how good (AUC close to 1) or how poor (AUC close to 0.5) a test is. If down-regulation was defined as oestradiol <40, <60 or <80 pg/ml, the AUC of 3D-ultrasound was 0.57, 0.83 and 0.97 respectively. The highest sensitivity (100%) and specificity (93.2%) of 3D-ultrasound was achieved if down-regulation was defined as oestradiol <80 pg/ml (n = 44), with an endometrial volume of 1.9 ml. If down-regulation was defined as oestradiol <60 pg/ml (n = 42) the best combination of highest sensitivity (95.2%) and specificity (75. 0%) was obtained with an endometrial volume of 1.9 ml. The comparison of 3D volume calculation with endometrial thickness measurement revealed no significant difference in predicting down-regulation. 3D volume estimation provides a new tool for diagnosing relative hypo-oestrogenism or down-regulation, but it was not superior to two-dimensional ultrasound.

Adult↗
PubMed1999

Elective transfer of embryos selected on the basis of first polar body morphology is associated with increased rates of implantation and pregnancy.

OBJECTIVE: To determine the relationship between first polar body morphology and implantation rate and pregnancy rate (PR), to facilitate decision making concerning elective ET. DESIGN: Prospective, randomized study. SETTING: Fertility center. PATIENT(S): One hundred fifty-eight consecutive patients (173 intracytoplasmic sperm injection cycles) resulting in embryo transfers. INTERVENTION(S): In our study group, priority in ET was given to embryos derived from well-shaped first polar bodies, whereas selection of embryos for transfer in the control group was based exclusively on the degree of embryo fragmentation. MAIN OUTCOME MEASURE(S): Total numbers of implantations and pregnancies, PR and implantation rate, and rates of multiple pregnancy and miscarriage. RESULT(S): In the study cohort, 212 embryos were transferred. In the control group, 313 embryos were transferred. The implantation rate and PR were significantly lower in the control group than in the study cohort. In addition, the rate of multiple pregnancy was significantly higher in the study group. CONCLUSION(S): Elective transfer of embryos selected on the basis of first polar body morphology results in higher implantation and pregnancy rates. Multiple pregnancy can be avoided by transferring a reduced number of embryos selected on the basis of first polar body morphology.

Adult↗
PubMed1999

Reproducibility of transvaginal three-dimensional endometrial volume measurements during ovarian stimulation.

Before estimating the clinical role of a method, the reproducibility has to be evaluated precisely. This study aimed to document the reproducibility of the endometrial volume measurement by three-dimensional (3D)-ultrasound. The volume measurements were done on 57 consecutive in-vitro fertilization (IVF) patients with either the full planar (contour) or the three distance method. A paired t-test provided no statistically significant difference between the two methods. Linear regression analysis, using the full planar method as independent and the other as dependent variables, yielded the following results: intercept = 0.348, not statistically different from 0; slope = 0.962, statistically different from 1 (P < 0.01). Interobserver reliability for the three distance method was 0.6667 and for the full planar method was 0.9565. Intra-observer reliability for the three distance method was 0.8426 and for the full planar method 0.9394. The correspondence between and within observers seemed to be good. Both methods are reliable, but the full planar method seems to provide slightly better reproducibility in regard to endometrium volume measurement.

Adult↗
PubMed1998

[Doppler ultrasound of the umbilical vein in fetal 3rd degree atrioventricular block].

A 21 week fetus was diagnosed with complete heart block. From the first diagnosis until 38 weeks gestation, umbilical venous pulsations occurred during ventricular systole. The ventricular frequency was 49 bpm. The venous pulsations corresponded with the ventricular frequency. At 38 weeks venous pulsations also occurred during ventricular diastole. Umbilical pulsations during diastole were associated with a decrease of ventricular frequency to 28 bpm and fetal hydrops. The venous pulsations during ventricular systole seem to be characteristic of complete heart block. The pulsations during ventricular diastole reflect the fetal heart failure. Doppler ultrasound aids in the diagnosis and surveillance of the fetus with complete heart block.

Adult↗
PubMed1997

[Fetal outcome in reduced flow in the ductus venosus during atrial contraction].

OBJECTIVE: To document the fetal outcome in cases with pathologic Doppler findings in the fetal ductus venosus. METHODS: The outcome of 12 fetuses with reduced velocities in the ductus venosus during atrial contraction was analyzed retrospectively and compared with that of a group of 57 fetuses with normal flow velocities in the umbilical artery and in the fetal ductus venosus. RESULTS: The perinatal mortality was higher in the group with pathologic Doppler findings. There was no significant difference of pH (7.20 vs. 7.24) and Apgar scores (7.57 vs. 8.36) of survivors between the two groups. All 12 fetuses showed increased retrograde velocities in the inferior vena cava. Seven fetuses showed umbilical vein pulsations. CONCLUSIONS: The diagnosis of altered velocities in the ductus venosus may influence prenatal decisions. Therefore Doppler examinations of the fetal ductus venosus should be performed in high-risk pregnancies.

Adult↗
PubMed1996

[The polyhydramnios symptom: analysis of 56 cases].

Analysis of 56 CASES: 56 cases of polyhydramnios, which were diagnosed sonographically over a period of three years, were analysed retrospectively in this study. In 9334 births, the prevalence of this symptom was 0.6%. Malformations were the most common cause (26.7%) of polyhydramnios (p < 0.001). In comparison to our normal patient group gestational diabetes, twin pregnancies with elevated amniotic fluid of one twin, virus infections, fetal chromosome abnormalities were diagnosed at a significantly higher rate (p < 0.001). The perinatal mortality rate (28.5%) in comparison to our normal collective (1.6%) was also significantly higher. Because of the high mortality, polyhydramnios must be assessed precisely and treated if possible. Fetal karyotyping should be routinely performed in the second trimester.

Amniocentesis↗
PubMed1996

[Venous Doppler in non-immunologic hydrops fetalis].

Fifteen fetuses with nonimmune hydrops underwent venous Doppler examinations of inferior vena caval flow. The results were analysed retrospectively. Increased retrograde inferior vena caval flow was defined as pathological (> 15% as anterograde flow). This finding correlates with reduced fetal cardiac output. Nine of fifteen fetuses had increased retrograde flow of inferior vena cava. In comparison to the group with physiologic Doppler parameters the perinatal mortality was significantly higher (p < 0.027) in the group with increased retrograde flow of the inferior vena cava. This and other results as well as the rate of remission underline the value of venous Doppler in predicting fetal outcome.

Blood Flow Velocity↗
PubMed1996

[Tetralogy of Fallot with absent pulmonary valve--prenatal diagnosis and management in the 2nd trimester].

Tetralogy of Fallot with absent pulmonary valve is a rare congenital cardiac malformation detected in 3% to 6% of tetralogy of Fallot patients. The prognosis depends on respiratory complications. In the present case the diagnosis was made at 18 week's gestation with two-dimensional and Doppler echocardiography. A ventricular septal defect and overriding aorta, absent valve echo, pulmonary regurgitation, and cystic pulsatile dilatation of the left pulmonary artery were the main diagnostic criteria. Severe respiratory complications were assumed in combination with a hyperechogenic left lung and termination of pregnancy was performed at 20 weeks' of gestation.

Abortion, Eugenic↗
PubMed1996

Severe ovarian hyperstimulation syndrome and combined intrauterine and tubal pregnancy after in-vitro fertilization and embryo transfer.

Ovarian hyperstimulation syndrome (OHSS) and heterotopic pregnancy are two well recognized entities occurring after in-vitro fertilization (IVF). This is the first reported case of a severe OHSS and coexistent heterotopic pregnancy after IVF and embryo transfer. Diagnosis of tubal pregnancy was obscured both by stimulated ovaries which prevented accurate ultrasound definition and the coexistence of an intrauterine pregnancy which accounted for human chorionic gonadotrophin (HCG) concentrations and also for aggravation of the OHSS. The roles of transvaginal ultrasound, diagnostic laparoscopy and early paracentesis in the management of this rare complication of assisted reproductive technologies are discussed.

Adult↗
PubMed1995

[Hemodilution in treatment of intrauterine dystrophy].

It was the aim of the study to show that HES (Hydroxy-Ethyl-Starch) in intrauterine dystrophy identified by ultrasonography can increase fetal growth. Twenty pregnant women were treated in two groups (outpatients versus inpatients). Clinically, the result was satisfying.

Adult↗