Welcome to The Visible Embryo



Home-- -History-- -Bibliography- -Pregnancy Timeline- --Prescription Drugs in Pregnancy- -- Pregnancy Calculator- --Female Reproductive System- -Contact

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.

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!




Pregnancy Timeline

Prescription Drug Effects on Pregnancy

Pregnancy Calculator

Female Reproductive System

Contact The Visible Embryo

News Alerts Archive

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.
Content protected under a Creative Commons License.

No dirivative works may be made or used for commercial purposes.


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
Google Search artcles published since 2007

Home | Pregnancy Timeline | News Alerts |News Archive Dec 4, 2013


Fetal Alcohol Syndrome (FAS) or Fetal Alcohol Spectrum Disorders (FASD)
can be directly related to as few as one drink during pregnancy.

Image credit: University of California Santa Barbara Sex Info website

WHO Child Growth Charts




Prenatal alcohol exposure disrupts brain & behavior

Researchers have long known that ethanol exposure from alcohol impacts brain and cognitive development in infants, but not until now demonstrated the connection between exposure and disruption to neural networks leading to changes in behavior.

Prenatal exposure to alcohol severely disrupts major features of brain development that potentially lead to increased anxiety and poor motor function, conditions typical in humans with Fetal Alcohol Spectrum Disorders (FASD), according to neuroscientists at the University of California, Riverside.

In groundbreaking work, scientists at the University of California at Riverside discovered prenatal exposure to alcohol significantly alters the expression of genes and the development of connections in the neocortex — the part of the brain responsible for high-level thought and cognition, vision, hearing, touch, balance, motor skills, language, and emotion — in a mouse model of FASD.

Prenatal alsohol exposure causes areas of the neocortex to be misconnected to each other, researchers found.

These findings contradict a recently popular belief that consuming alcohol during pregnancy does no harm.

“If you consume alcohol when you are pregnant you can disrupt the development of your baby’s brain,” said Kelly Huffman, assistant professor of psychology at UC Riverside and lead author of the study.

The work appears in the Nov. 27 issue of The Journal of Neuroscience, the official, peer-reviewed publication of the Society of Neuroscience. Study co-authors are UCR Ph.D. students Hani El Shawa and Charles Abbott.

Huffmann: “This research helps us understand how substances like alcohol impact brain development and change behavior. It also shows how prenatal alcohol exposure generates dramatic change in the brain that leads to changes in behavior. Although this study uses a moderate- to high-dose model, other studies have shown that even small doses alter development of key receptors in the brain.”

Huffman’s team found dramatic changes in intra-neocortical connections between the frontal, somatosensory and visual cortex in mice born to mothers who consumed ethanol during pregnancy.

The changes were especially severe in the frontal cortex, which regulates motor skill learning, decision-making, planning, judgment, attention, risk-taking, executive function and sociality.

The neocortex region of the mammalian brain is similar in mice and humans, although human processing is more complex. In previous research, Huffman and her team created what amounts to an atlas of the neocortex, identifying the development of regions, gene expression and the cortical circuit over time.

Her research is part of the foundation to understanding behavioral disorders such as autism and FASD.

Children diagnosed with FASD may have facial deformities and can exhibit cognitive, behavioral and motor deficits from ethanol-related neurobiological damage in early development. Those deficits may include learning disabilities, reduced intelligence, mental retardation and anxiety or depression, Huffman said.

Milder forms of FASD may produce no facial deformities, such as wideset eyes and smooth upper lip, but behavioral issues such as hyperactivity, hyperirritability and attention problems as the child develops.

Based on her earlier research, Huffman expected to find some disruption of intraneocortical circuitry, but thought it would be subtle.
“I was surprised that the result of alcohol exposure was quite dramatic. We found elevated levels of anxiety, disengaged behavior, and difficulty with fine motor coordination tasks. These are the kinds of things you see in children with FASD.”

The next phase of Huffman's research will examine whether deficits related to alcohol prenatal exposure continue in subsequent generations.

The bottom line, Huffman adds, is that women who are pregnant or who are trying to get pregnant should abstain from drinking alcohol.

“Would you put whiskey in your baby’s bottle? Drinking during pregnancy is not that much different," says Huffman.

“If you ask me if you drink three glasses of wine during pregnancy - will your child have FASD, I would say 'probably not.'

If you ask me if there will be changes in the child's brain, I would say - 'probably yes.'

"There is no safe level of drinking during pregnancy.”

In utero ethanol exposure from a mother's consumption of alcoholic beverages impacts brain and cognitive development, creating a range of deficits in the child (Levitt, 1998; Lebel et al., 2012). Children diagnosed with fetal alcohol spectrum disorders (FASD) are often born with facial dysmorphology and may exhibit cognitive, behavioral, and motor deficits from ethanol-related neurobiological damage in early development. Prenatal ethanol exposure (PrEE) is the number one cause of preventable mental and intellectual dysfunction globally, therefore the neurobiological underpinnings warrant systematic research. We document novel anatomical and gene expression abnormalities in the neocortex of newborn mice exposed to ethanol in utero. This is the first study to demonstrate large-scale changes in intraneocortical connections and disruption of normal patterns of neocortical gene expression in any prenatal ethanol exposure animal model. Neuroanatomical defects and abnormal neocortical RZRβ, Id2, and Cadherin8 expression patterns are observed in PrEE newborns, and abnormal behavior is present in 20-d-old PrEE mice. The vast network of neocortical connections is responsible for high-level sensory and motor processing as well as complex cognitive thought and behavior in humans. Disruptions to this network from PrEE-related changes in gene expression may underlie some of the cognitive-behavioral phenotypes observed in children with FASD.

Received August 30, 2013.
Revision received October 22, 2013.
Accepted October 23, 2013.