Oocytes were obtained from patients with tubal infertility at fixed times after the onset of the endogenous LH rise or hCG injection, and were inseminated immediately after recovery or after periods of 4-4 1/2, 5-5 1/2 and 6-6 1/2 h in culture in vitro. Delayed insemination resulted in a marked increase in the proportion of oocytes that were fertilized and developed to normal embryos and maximum rates occurred after 5-5 1/2 h in culture (0-1/2 h, 26%; 4-4 1/2 h, 50%; 5-5 1/2 h, 89%; 6-6 1/2 h, 69%). The range and mean (+/- s.d.) intervals from insemination for the pronuclear and early cleavage stages were 27-43 (35.6 +/- 4.4) h for 2-cell stages, 36-65 (45.7 +/- 8.3) h for 4-cell stages, 45-73 (54.3 +/- 12.6) h for 8-cell stages and 68-85 h for the 16-cell stage. In 7/50 patients receiving 1 or 2 embryos at the 2-, 4- and 8-cell stages, fetal development was normal and 2 women had twin pregnancies (36% success compared with 8% for single embryos). All pregnancies were from the groups in which insemination was delayed for 5-6 1/2 h. It is concluded that a short period of culture in vitro may allow the completion of oocyte maturation, and improve the results of in-vitro fertilization.

/pdf/effect-of-delayed-insemination-on-in-vitro-fertilization-5bkqgba4q0.pdf

Effect of delayed insemination on in-vitro fertilization, culture and transfer of human embryos.

https://www.genetics.org/content/genetics/78/1/395.full.pdf

Embryo Banks in the Future of Developmental Genetics

The incorporation of labelled precursors into mouse embryo RNA has been studied by column chromatography and the use of sucrose gradients. The synthesis of new ribosomal and 4S RNA can be detected at the four cell stage.

RNA synthesis during early development of the mouse.

1. On the 4th day of gestation, embryos were recovered from mice of the C57BL, R III, JU, C3H and Q strains, and cell counts were carried out. Significant differences between strains were seen, both in the percentage of embryos which had reached the blastocyst stage, and in the mean number of cells per embryo. C57BL embryos had most cells, and C3H embryos fewest. 2. Examination of earlier stages of C57BL and C3H development showed that the proportionate difference in cell number remained constant, so that the difference involved the time at which cleavage began, and not the rate of cleavage. Activation of the eggs and the formation of pronuclei also occurred earlier in C57BL than in C3H females. 3. The difference in cell number between C57BL and C3H embryos did not depend on a difference in time of mating, nor on the genotype of the male, since reciprocal crosses were similar to the maternal strain. The difference was maintained in culture from the two-cell stage.

Genetic effects on the timing of early development in the mouse.

There has been suggestive evidence for embryonic genome activity in the preimplantation mouse embryo for several years. Whitten and Dagg (1961) found a paternal effect on cleavage rate before implantation, and Morris (1968) suggested that the X chromosome is necessary for early cleavage. However, to prove the presence of paternally derived gene activity, it is necessary to demonstrate the existence of a protein in the embryo coded for by a paternal allele. Chapman et al. (1971) have recently shown the presence on day 5 of development of the paternal variant of glucose phosphate isomerase (GPI) in mouse embryos derived by mating males and females containing the genes for different isozyme subunits. In addition, the work of Epstein (1972) on the total activity of hypoxanthine-guanine phosphoribosyl transferase suggests that the paternal allele for this enzyme, which is sex linked, is active at day 4 in development. Work in our laboratory during the past 2 years has also identified the paternal variant of GPI in the mouse embryo but at an earlier stage of development than previously reported. The studies reported here demonstrate paternal allele activity of GPI on the third day of development after only three cleavage divisions. This is not only earlier than previously reported for the mouse but is much earlier than found in fish, frog, and quail.

Parental Glucose Phosphate Isomerase Activity in Three-Day Mouse Embryos

Influence of spermatozoa on the cleavage rate of mouse eggs.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

C. P. Dagg

Author Tools

Chat about Author

Papers

Influence of spermatozoa on the cleavage rate of mouse eggs.