The effectiveness of blastocyst culture and transfer in human in-vitro fertilization (IVF) was evaluated in a prospective randomized trial in patients having a moderate to good response to ...gonadotrophin stimulation. Embryos were transferred either on day 3 after culture to around the 8-cell stage in Ham's F-10 medium supplemented with fetal cord serum, or on day 5 after culture to the blastocyst stage in the sequential serum-free media G 1.2 and G 2.2. The pregnancy rates after transfer on day 3 or day 5 were equivalent, 66 and 71% respectively; however, significantly more embryos were transferred on day 3 (3.7) than on day 5 (2.2). The number of blastocysts transferred did not affect the implantation rate, and pregnancy rates when either two or three blastocysts were transferred were 68 and 87% respectively. The implantation rate of the blastocysts (50.5% fetal heart beat) was significantly higher compared to the cleavage stage embryos transferred on day 3 (30.1%). The percentage of blastocyst development was not affected by the number of 2-pronuclear embryos, or by maternal age. Irrespective of the number of blastocysts formed, pregnancy rates were similar. Furthermore, the pregnancy rate following blastocyst transfer in patients with 10 or more follicles at the time of human chorionic gonadotrophin administration was not affected by patient age. More than 60% of patients having blastocyst culture and transfer had supernumerary embryos for cryopreservation. The establishment of a pregnancy following thaw and transfer confirmed the viability of cryopreserved blastocysts cultured in the absence of serum or co-culture. The ability to transfer just two blastocysts while maintaining high pregnancy rates will therefore help to eliminate high order multiple gestations and improve the overall efficiency of human IVF.
Among 40 states with sufficient numbers of black infant deaths to generate reliable rates for the years 2002-04, Wisconsin had the highest black infant mortality rate (IMR) at 17.6 deaths per 1,000 ...live births, approximately three times the state rate for whites. However, in contrast to trends in Wisconsin and the other 39 states, the black IMR in Dane County WI, has declined substantially, achieving parity with whites and meeting Healthy People 2010 objective 16-1 for reducing fetal and infant deaths. Here, Schlenker and Ndiaye report how the Public Health Madison Dane County (PHMDC) analyzed approximately 100,000 birth and death records from 1990 through 2007 for birthweight, gestational age, prenatal care, and other infant mortality risk factors. Among other things, a CDC editorial note is included.
Abstract
Study question
Can increased time in thaw solution improve oocyte survival and outcomes following vitrification/warming?
Summary answer
Exposing vitrified oocytes to the first step thawing ...solution for 90 seconds improved oocyte survival compared to 60 second exposure.
What is known already
Oocytes are a sensitive cell type and careful handling of the cells is required to obtain high outcomes following vitrification and warming. Carefully timed exposure to various vitrification solutions is required to avoid toxicity and ensure proper vitification. Similarly, proper and carefully timed exposure to warming solutions is required to avoid oocyte damage upon warming. Recent reports suggest a modified and rapid warming protocol may be beneficial for vitrified blastocysts. However, oocytes are unique cells and may require unique considerations to optimize warming.
Study design, size, duration
Retrospective analysis of donor oocyte warming outcome data within a single IVF lab over a 12 month period comparing a 60 second first step during oocyte warming (control n = 637 oocytes) versus a very consistent 90 second exposure (n = 672 oocytes) to the first step thawing solution.
Participants/materials, setting, methods
Human donor oocytes were vitrified using the standard Kitazato protocol with ES drop merging and loading on CryoTop devices using the wicking method prior to plunging into liquid nitrogen. Warming was performed using the standard protocol of 60 seconds in thaw solution (TS) or 90 seconds exposure. All cycles utilized ICSI and excluded testicular sperm samples. Survival, fertilization and blastocyst development were compared between the two exposure groups. Data were analyzed utilizing Fisher’s Exact Test.
Main results and the role of chance
Oocyte survival differed between the two timing treatments, with exposure to TS for 90 seconds yielding higher oocyte survival (96.1%) than 60 secondsTS exposure (92.0%), p < 0.002. No differences in fertilization following ICSI (78.3.0% vs. 79.0%) orin good quality blastocyst conversion (≥3BB) on day 5 (22.1% vs. 25.1%) or by day 7 (55.3% vs. 55.7%) were apparent. The aneuploidy rate of blastocysts were similar, with 28.5% in the 90 second TS treatment group and 27.3% in the 60 second TS exposure group.
Limitations, reasons for caution
Data were examined retrospectively and sibling oocyte splits were not utilized. Clinical outcomes following resulting embryo transfer were not examined.
Wider implications of the findings
These data may help improve oocyte warming protocols and resulting outcomes.
Trial registration number
not applicable
This study reports on the evolution of Cu(In,Ga)Se
2 film surface orientation during growth and on the substrate influence on the resulting film texture. A thermal evaporation process deposits 0.5–1 ...μm thick Cu-poor Cu(In,Ga)Se
2 layers with constant deposition rates of all elements during growth on Mo single crystals, polycrystalline Mo, and highly oriented pyrolytic graphite. X-ray diffraction measurements allow the determination of the film texture. On highly oriented pyrolytic graphite, on (100)-oriented Mo, and on (111)-oriented Mo surfaces Cu(In,Ga)Se
2 grows with a pure (112) surface orientation, whereas on (110)-oriented Mo single crystals the (220/204) Cu(In,Ga)Se
2 surface orientation dominates. On polycrystalline Mo substrates, no significant preferred film orientation for layers up to 1 μm thickness exists for as-grown films. Annealing of Cu(In,Ga)Se
2 films on polycrystalline Mo substrates leads to an increase of the mean grain size and to an evolution of a (112) preferred film orientation. The pure (112) texture of the Cu(In,Ga)Se
2 film grown on highly oriented pyrolytic graphite which hardly interacts with the adsorbed material proves that the (112) surface orientation is energetically preferred. Among the investigated single crystalline Mo substrates, only (110)-oriented Mo has an impact on the resulting Cu(In,Ga)Se
2 film texture. This substrate influence and the fact that (112)-oriented grains grow at the expense of other orientations reveal why Cu(In,Ga)Se
2 films grow on polycrystalline Mo with no preferred orientation during early stages of growth but result in a (112) texture for later growth stages.
Hepatitis A is a common vaccine-preventable disease in the United States. Most cases occur during community-wide outbreaks, which can be difficult to control. Many case-patients have no identified ...source.
To identify foodborne and household sources of hepatitis A during a community-wide outbreak.
Serologic and descriptive survey.
Salt Lake County, Utah.
A total of 355 household contacts of 170 persons reported with hepatitis A during May 1996 to December 1996, who had no identified source of infection; and 730 food handlers working in establishments where case-patients had eaten.
Prevalence of immunoglobulin M antibodies to hepatitis A virus (IgM anti-HAV) among household and food service contacts.
Overall, 70 household contacts (20%) were IgM anti-HAV-positive, including 52% of children 3 to 5 years old and 30% of children <3 years old. In multivariate analysis, the presence of a child <3 years old (odds ratio OR: 8.8; 95% confidence limit CL: 2.1,36) and a delay of >/=14 days between illness onset and reporting (OR: 7. 9; 95% CL: 1.7,38) were associated with household transmission. Of 18 clusters of infections linked by transmission between households, 13 (72%) involved unrecognized infection among children <6 years old. No food handlers were IgM anti-HAV-positive.
During a community-wide outbreak, HAV infection among children was common, was frequently unrecognized, and may have been an important source of transmission within and between households. Transmission from commercial food establishments was uncommon. Ongoing vaccination of children may prevent future outbreaks.
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