A.N. Sallam

Impact of Technical Difficulties, Choice of Catheter, and the Presence of Blood on the Success of Embryo Transfer—Experience from a Single Provider

AbstractPurpose: To investigate the impact of technical difficulties, choice of catheter, and the presence of blood during embryo transfer on the results of in vitro fertilization and ICSI. Methods: A cohort of 784 consecutive cycles in 655 in vitro fertilization and ICSI patients were studied. Results: Negotiating the cervix, using the volsellum, presence of blood on the catheter wall or on the cervix did not affect the results. Changing the catheter and blood on the catheter tip reduced the pregnancy (P < 0.05 and P < 0.05) and implantation rates (P < 0.001 and P < 0.01). The Ultrasoft catheter produced higher pregnancy (P < 0.0005) and implantation rates (P < 0.01) compared to the more rigid Frydman catheter. Conclusions: Negotiation of the cervix, the use of a volsellum, and the presence of blood on the catheter wall or on the cervix do not affect the results. Changing the catheter and blood on the catheter tip significantly diminish the pregnancy and implantation rates. Soft catheters perform better.

Reference values for the midluteal plasma progesterone concentration: evidence from human menopausal gonadotropin-stimulated pregnancy cycles.

OBJECTIVE To determine reference values for the midluteal plasma progesterone concentration. DESIGN Retrospective analysis. SETTING Infertility clinic at an academic medical center. PATIENT(S) One hundred ninety-two infertile women who became pregnant after induction of ovulation with hMG. INTERVENTION(S) The plasma progesterone level was measured during the midluteal phase of the hMG treatment cycle. MAIN OUTCOME MEASURE(S) The midluteal plasma progesterone concentration was correlated with the outcome of the pregnancy. RESULT(S) In this cohort of 192 women in whom ovulation was induced with hMG and 5,000 IU of hCG, the mean midluteal plasma progesterone concentrations were 29.07 ng/mL, 25.85 ng/mL, 31.49 ng/mL, 41.39 ng/mL, and 28.64 ng/mL in all cycles that resulted in pregnancy, cycles that resulted in full-term singleton pregnancy, cycles that resulted in full-term multiple pregnancy, cycles that resulted in preterm pregnancy, and cycles that ended in miscarriage, respectively. There was no statistically significant difference in the progesterone concentration between the cycles that resulted in full-term pregnancy and those that ended in miscarriage, but there was a statistically significant difference between the cycles that resulted in singleton pregnancy and those that resulted in multiple pregnancy. The minimum value that was compatible with a full-term pregnancy in this cohort of women was 10.83 ng/mL. CONCLUSION(S) In a cohort of 192 women, the minimum plasma progesterone concentration on day 7 in women who attained a full-term pregnancy after induction of ovulation with 5,000 IU of hCG was 10.83 ng/mL.

New measurement technique for modular multilevel converter with IGBT open-circuit failure detection and tolerance control for three-level submodule

Modular multilevel converter (MMC) served as a promising converter for High Voltage Direct Current (HVDC) transmission. However, reliability is one of the most important challenges. Redundant submodules (SMs) are often used to replace the faulty SMs to ensure continuous operation of the scheme and increase the system reliability. In this paper, a fault detection and clearance is proposed for three level SMs topology without additional voltage sensors or complex algorithms. The fault is detected using a measurement technique that has half the number of voltage sensors compared to conventional half-bridge. The main advantage of the proposed technique is the reduction of the number of voltage sensors with full estimation for the capacitors voltages. Moreover, it provides fault detection and tolerance control. A simulation model has been implemented to validate the proposed technique and to evaluate its performance.

The value of sperm velocity, strict morphology and the hypo-osmotic swelling test as predictors of the sperm fertilization potential.

BACKGROUND: Although prevalence of infertility is high and are predominantly or partly due to a male factor, the diagnostic tools in male fertility are insufficient being mainly based on the evaluation of sperm concentration, motility and morphology . These parameters are, however, poorly standardized, subjective) and not powerful predictors of fertility. OBJECTIVE: The aim of this work was to evaluate the sperm velocity characteristics, the sperm morphology assessment determined by strict criteria and the hypo-osmotic swelling (HOS) test as predictors of sperm fertilization potential. MATERIALS ANDMETHODS: A comparison of 3 parameters to determine which of them is a better predictor of the fertilization potential of a given semen sample in the IVF model, namely the sperm velocity characteristics determined by computerised semen analysis, strict sperm morphology and the HOS test. Data from 58 couples attending the assisted conception unit for conventional in-vitro fertilization (IVF) treatment were analyzed. Simple linear regression and multiple stepwise regression analysis were performed taking the fertilization rate as the dependent variable and the following as independent variables: (1) female partner’s age, (2) number of human menopausal gonadotropin (hMG) ampoules, (3) sperm count, (4) grade A motility, (5) grade B motility, (6) grade C motility, (7) grade A+B motility, (8) mean sperm velocity, (9) linear velocity, (10) linearity index, (11) strict morphology and (12) the HOS test. The results were used to calculate the cut-off levels for the statistically significant predictors of fertilization. RESULTS: Only themean sperm velocity and the strict spermmorphology assessment showed significant correlation with the fertilization rate. The cutoff values were a mean sperm velocity of 16 mm/sec and a strict sperm morphology of 10 %. A minimum sperm velocity of 13 mm/sec and a minimum strict sperm morphology of 2 % were necessary to achieve fertilization in 50% of the oocytes. The results of the HOS test did not correlate with the fertilization rate. CONCLUSIONS: Sperm velocity and strict spermmorphology evaluation are good predictors of fertilization potential. The HOS test is not a good predictor of fertilization potential.