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Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than ' million visitors each month.

WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a new Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!




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Disclaimer: The Visible Embryo web site is provided for your general information only. The information contained on this site should not be treated as a substitute for medical, legal or other professional advice. Neither is The Visible Embryo responsible or liable for the contents of any websites of third parties which are listed on this site.
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Pregnancy Timeline by SemestersFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresFemale Reproductive SystemEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterSecond TrimesterFirst TrimesterFertilizationDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
May 13, 2011--------News Archive

Expectant Fathers Need Prenatal Care and Support
Research has found that stress related to pregnancy uniquely affects the health of expectant fathers, which in turn, influences the health of expectant mothers and their infants.

Found: New Gene That Causes Intellectual Disability
Scientists have identified a gene that, when defective, leads to Joubert syndrome.

May 12, 2011--------News Archive

Cryopreserved Umbilical Cord Blood Same As Fresh
The study gives hope that long term storage of umbilical cord stem cells will not affect their ability to act as a reservoir for other potentially beneficial cell types.

High Pregnancy BPA Results In Infant Abnormalities
Study advises pregnant women to reduce exposure levels to BPA.

May 11, 2011--------News Archive

15 Eggs Perfect Number To Achieve Birth After IVF
UK research has shown that doctors retrieving about 15 eggs in a single cycle have the best chance of achieving a live birth after assisted reproduction.

Depression Treated Well In Moms Benefits Her Kids
In fact, the faster mothers got better, the faster their kids improved – and the greater the degree of improvement experienced.

May 10, 2011--------News Archive

Scientists Reveal Nerve Cells' Navigation System
Scientists have discovered how two closely related proteins guide projections from nerve cells with exquisite accuracy.

Stem Cell Technology Used In Unique Surgery
For the first time ever in the world, researchers have produced a blood vessel from stem cells and then used it in an operation on a 10-year-old girl.

May 9, 2011--------News Archive

Mayo Clinic Turns Zebrafish Genes Off and On
Researchers plan to use information from this study for a gene codex that could serve as a reference for information stored in all vertebrate animal genomes.

Autism in South Korea Estimated at 1 in 38 Children
The study identifies children not yet diagnosed and has the potential to increase autism spectrum disorder prevalence estimates worldwide.

WHO Child Growth Charts

An analysis of over 400,000 IVF cycles in the UK has shown that doctors should aim to retrieve around 15 eggs from a woman's ovaries in a single cycle in order to have the best chance of achieving a live birth after assisted reproduction technology.

The study, which is published online in Europe's leading reproductive medicine journal Human Reproduction [1], found that there was a strong relationship between live birth rates and the number of eggs retrieved in one cycle. The live birth rate rose with an increasing number of eggs up to about 15; it levelled off between 15 and 20 eggs, and then steadily declined beyond 20 eggs.

One of the authors of the study, Dr Arri Coomarasamy, said: "This is the first study to look at the association between the number of eggs and live births. Some smaller studies have reported previously on the association between egg numbers and pregnancy rates, but not live births. This is also the first study to devise a graph that can be used by patients and clinicians to estimate the chances of a live birth for a given number of eggs."

Dr Coomarasamy, a Clinical Reader and Consultant in Reproductive Medicine and Surgery at the University of Birmingham (UK), and his colleagues analysed data from the UK's Human Fertilisation and Embryology Authority (HFEA) on 400,135 IVF cycles that took place anywhere in the UK between April 1991 and June 2008.

As live birth rates have steadily improved during this period, the researchers used data from 2006 to 2007 to create a predictive model that most closely reflected current practice. Using the model, they created a mathematical graph, called a nomogram, which shows the relationship between women's age, the numbers of eggs retrieved and the predicted live birth rate. Now patients and clinicians can use the nomogram when making decisions about the degree of ovarian stimulation required to achieve the optimum number of eggs for a live birth.

"Our data show that around 15 eggs may be the best number to aim for in an IVF cycle in order to maximise the chances of a live birth while minimising the risk of ovarian hyperstimulation syndrome (OHSS) which is associated with a high number of eggs, usually over 20," said Dr Coomarasamy. "Mild stimulation protocols aim to retrieve less than six to eight eggs; a standard stimulation should aim for 10-15 eggs, and we believe this is what is associated with the best IVF outcomes; when the egg number exceeds 20, the risk of OHSS becomes high." [2]

He believes that doctors could combine the use of the nomogram with current methods of measuring a woman's ovarian reserve in order to work out how much her ovaries need to be stimulated in order to retrieve 15 eggs in a safe manner.

"There are tests of ovarian reserve such as anti-mullerian hormone (AMH) and antral follicle count (AFC) which are good at predicting ovarian response and the egg yield following ovarian stimulation during IVF treatment. However, AMH and AFC are not good predictors of live birth rates. If clinicians use AMH or AFC to estimate the egg yield, they can then use our nomogram to convert this estimated number of eggs into a predicted live birth rate, thus completing the prognostic chain to estimate the chances of what both they and the women want: a live born baby."

The data also showed that during 2006-2007 the predicted live birth rate for women with 15 eggs retrieved was 40% for those aged 18-34, 36% for those aged 35-37, 27% for those aged 38-39 and 16% for women aged 40 and over.

Currently the HFEA collects data in a way that does not allow researchers to link information on IVF cycles using fresh embryos with IVF cycles using frozen embryos in the same woman. The authors of the study say that it is possible that this might alter the declining effect of higher numbers of eggs on fresh IVF cycles, because a woman has a greater chance of becoming pregnant if frozen embryos are available for transferring in subsequent cycles.

However, "existing data suggest that the numbers of embryos frozen after a fresh IVF cycle are not enhanced by retrieving more than 18 eggs," write the authors.

Dr Coomarasamy said: "The HFEA have agreed to provide data linking fresh and frozen cycles to answer this research question and they may be releasing this information soon. By including the outcome following replacement of all frozen embryos generated from a single fresh IVF treatment, we could give an estimate of the cumulative live birth rate per IVF cycle. This is important information and we hope to gather the necessary data and report on this outcome in the future.

"None of this work would be possible without the support of the HFEA and we are very grateful to the staff there who validated these data."

[1] "Association between the number of eggs and live birth in IVF treatment: an analysis of 400 135 treatment cycles", by Sesh Kamal Sunkara, Vivian Rittenberg, Nick Raine-Fenning, Siladitya Bhattacharya, Javier Zamora, Arri Coomarasamy. Human Reproduction journal. doi:10.1093/humrep/der106

[2] Ovarian hyperstimulation syndrome (OHSS) is an excessive response by the ovaries in response to hormone drugs administered to stimulate the production of eggs for collection for IVF cycles. Mild and moderate OHSS causes abdominal pain, swelling and sometimes nausea and vomiting. In the rare, severe cases, it is a life-threatening medical emergency, with massive ovarian enlargement, fluid accumulation in the abdominal and pleural cavities, and risk of thrombosis.