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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 one million visitors each month.

Today, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than 1 million visitors each month. The field of early embryology has grown to include the identification of the stem cell as not only critical to organogenesis in the embryo, but equally critical to organ function and repair in the adult human. The identification and understanding of genetic malfunction, inflammatory responses, and the progression in chronic disease, begins with a grounding in primary cellular and systemic functions manifested in the study of the early embryo.

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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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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 ON weeks 0 - 40 and follow along every 2 weeks of fetal development
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Home | Pregnancy Timeline | News Alerts |News Archive July 11, 2014

Current birthweight graphs are based on children of Western European descent — a standard
which suggests many East Asian or South Asian newborns be classified as underweight,
when in fact they are "normal" for their mother's OR father's ethnic group.


WHO Child Growth Charts




Dad's ethnic origin influences child's birthweight

A father's ethnic background can influence a child's birthweight as much as the mother's ethnic background, a new study has found. Previous research had only shown that a mother's ethnic background can influence a baby's birthweight.

Dr. Joel Ray, physician and researcher at the Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada, has compiled birthweights among different ethnic groups to advance our knowledge of what constitutes "normal" for birth weight. Babies considered to be small or too large just before birth can trigger emergency medical interventions such as Cesarean deliveries.

Birthweight is one of the essential yardsticks used to measure a baby's progress in its first days and weeks after birth.

Current birthweight graphs are based on children of Western European descent.

This standard suggests many East Asian or South Asian newborns be classified as underweight, when in fact they are "normal" for their mother's ethnic group.

The new study shows a lower newborn weight can also result when the father is of Asian descent.

Knowing that ethnic backgrounds impact birthweights is particularly important in Canada with its growing number of mixed race families. Researchers led by Dr. Joel Ray, had previously developed the first "newborn weight curves" for specific ethnic groups across Canada, but only based their results on the infant mother's ethnicity.

Dr. Ray's new paper, published in the Journal of Epidemiology and Community Health, shows that babies born to a Asian-born mother and an Asian-born father weigh about six per cent less than those infants born to native Canadian parents.

Dr. Ray also examined if birthweights were influenced by communities where parents live. When immigrant parents live in neighbourhoods with a high concentration of people from their same ethnic group, their babies weigh less than those of Canadian-born parents — particularly male babies.

Dr. Ray's study was based on an examination of 692,301 births recorded with Vital Statistics in Ontario between 2002 and 2009.

Background The association between maternal ethnicity and newborn weight is understood. Less is known about the additional influence of paternal ethnicity and neighbourhood ethnic composition.

We studied 692 301 singleton live births of parents of Canadian, Bangladeshi, Sri Lankan, Pakistani, Indian, Filipino, Vietnamese, Korean, Hong Kong or Chinese birthplace. We used multivariable regression to calculate mean (95% CI) birthweight differences between infants of two Canadian-origin parents and (1) foreign-born mother and Canadian-born father, (2) Canadian-born mother and foreign-born father or (3) two foreign-born parents from the same country. We also stratified by high versus low same-ethnic concentration of the parent’s residence. We adjusted for gestational age at birth, maternal age, parity, marital status and income quintile.

Compared with male and female infants of two Canadian-born parents, those of same-country foreign-born parents weighed 6.2% (−218 g, 95% CI −214 g to −223 g) and 5.6% (−192 g, 95% CI −187 g to −196 g) less, respectively. The largest mean weight difference was among male (8.4% (−297 g, 95% CI −276 g to −319 g)) and female (8.2% (−279 g, 95% CI −262 g to −296 g)) infants of two Bangladeshi parents. Infants of a foreign-born mother and Canadian-born father had weights closest to those of two Canadian-born parents. Residing in an area of high (vs low) same-ethnic concentration was associated with lower birthweight among infants of mixed union couples, but not among those of parents originating from the same country.

Paternal and maternal ethnic origin influence newborn weight, which is modified by settlement in a high same-ethnic concentration area only among parents of mixed union.

This study received funding from the Canadian Institutes of Health Research and the SickKids Foundation.

About St. Michael's Hospital
St. Michael's Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future health care professionals in more than 23 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, and care of the homeless are among the hospital's recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Center, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael's Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.

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