Intrauterine instillation of diluted seminal plasma at oocyte pick-up does not increase the IVF pregnancy rate: a double-blind, placebo controlled, randomized study.

STUDY QUESTION Does intrauterine application of diluted seminal plasma (SP) at the time of ovum pick-up improve the pregnancy rate by ≥14% in IVF treatment? SUMMARY ANSWER Intrauterine instillation of diluted SP at the time of ovum pick-up is unlikely to increase the pregnancy rate by ≥14% in IVF. WHAT IS KNOWN ALREADY SP modulates endometrial function, and sexual intercourse around the time of embryo transfer has been suggested to increase the likelihood of pregnancy. A previous randomized double-blind pilot study demonstrated a strong trend towards increased pregnancy rates following the intracervical application of undiluted SP. As this study was not conclusive and as the finding could have been confounded by sexual intercourse, the intrauterine application of diluted SP was investigated in the present trial. STUDY DESIGN, SIZE, DURATION A single-centre, prospective, double-blind, placebo-controlled, randomized, superiority trial on women undergoing IVF was conducted from April 2007 until February 2012 at the University Department of Gynaecological Endocrinology and Reproductive Medicine, Heidelberg, Germany. PARTICIPANTS/MATERIALS, SETTING, METHODS The study was powered to detect an 14% increase in the clinical pregnancy rate and two sequential tests were planned using the Pocock spending function. At the first interim analysis, 279 women had been randomly assigned to intrauterine diluted SP (20% SP in saline from the patients' partner) (n = 138) or placebo (n = 141) at the time of ovum pick-up. MAIN RESULTS AND THE ROLE OF CHANCE The clinical pregnancy rate per randomized patient was 37/138 (26.8%) in the SP group and 41/141 (29.1%) in the placebo group (difference: -2.3%, 95% confidence interval of the difference: -12.7 to +8.2%; P = 0.69). The live birth rate per randomized patient was 28/138 (20.3%) in the SP group and 33/141 (23.4%) in the placebo group (difference: -3.1%, 95% confidence interval of the difference: -12.7 to +6.6%; P = 0.56). It was decided to terminate the trial due to futility at the first interim analysis, at a conditional power of 62%. LIMITATIONS, REASONS FOR CAUTION The confidence interval of the difference remains wide, thus clinically relevant differences cannot reliably be excluded based on this single study. WIDER IMPLICATIONS OF THE FINDINGS The results of this study cast doubt on the validity of the concept that SP increases endometrial receptivity and thus implantation in humans. STUDY FUNDING/COMPETING INTEREST(S) Funding was provided by the department's own research facilities. TRIAL REGISTRATION NUMBER DRKS00004615.

Influence of microphysical schemes on atmospheric water in the Weather Research and Forecasting model

This study examines how different microphysical parameterization schemes influence orographically induced precipitation and the distributions of hydrometeors and water vapour for midlatitude summer conditions in the Weather Research and Forecasting (WRF) model. A high-resolution two-dimensional idealized simulation is used to assess the differences between the schemes in which a moist air flow is interacting with a bell-shaped 2 km high mountain. Periodic lateral boundary conditions are chosen to recirculate atmospheric water in the domain. It is found that the 13 selected microphysical schemes conserve the water in the model domain. The gain or loss of water is less than 0.81% over a simulation time interval of 61 days. The differences of the microphysical schemes in terms of the distributions of water vapour, hydrometeors and accumulated precipitation are presented and discussed. The Kessler scheme, the only scheme without ice-phase processes, shows final values of cloud liquid water 14 times greater than the other schemes. The differences among the other schemes are not as extreme, but still they differ up to 79% in water vapour, up to 10 times in hydrometeors and up to 64% in accumulated precipitation at the end of the simulation. The microphysical schemes also differ in the surface evaporation rate. The WRF single-moment 3-class scheme has the highest surface evaporation rate compensated by the highest precipitation rate. The different distributions of hydrometeors and water vapour of the microphysical schemes induce differences up to 49 W m−2 in the downwelling shortwave radiation and up to 33 W m−2 in the downwelling longwave radiation.

Measurement of the electron neutrino charged-current interaction rate on water with the T2K ND280 π0 detector

This paper presents a measurement of the charged current interaction rate of the electron neutrino beam component of the beam above 1.5 GeV using the large fiducial mass of the T2K π0 detector. The predominant portion of the νe flux (∼85%) at these energies comes from kaon decays. The measured ratio of the observed beam interaction rate to the predicted rate in the detector with water targets filled is 0.89 ± 0.08 (stat.) ± 0.11 (sys.), and with the water targets emptied is 0.90 ± 0.09 (stat.) ± 0.13 (sys.). The ratio obtained for the interactions on water only from an event subtraction method is 0.87 ± 0.33 (stat.) ± 0.21 (sys.). This is the first measurement of the interaction rate of electron neutrinos on water, which is particularly of interest to experiments with water Cherenkov detectors.