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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.

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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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 March 4, 2014


Preterm delivery is directly associated with low birth weight.
Although in decline, the study is the first to identify low birth rate
with increased disease and change in response to drug treatment.

Image Credit: U.S. Department of Health and Human Services
Centers for Disease Control and Prevention
National Center for Health Statistics


WHO Child Growth Charts




How low birth weight affects the adult

Researchers have identified another concern related to low birth weight – a difference in how the body reacts to drugs, which may last a person’s entire life and further complicate treatment of illnesses or diseases that are managed with medications.

The findings add to the list of health problems that are already known to correspond to low birth weight, such as a predisposition for adult-onset diabetes, hypertension, and obesity.

The implication, researchers believe, is that low birth weight may not only cause increased disease, but it may also lessen the effectiveness of the drugs used to treat those diseases.

The research is among the first of its type to implicate low birth weight as a permanent factor in drug response. It was published in the European Journal of Pharmacology, by researchers from Oregon State University and Oregon Health & Science University. Funding was provided by both universities and the National Institutes of Health.

When more fully understood, low birth weight may be added to the list of factors already being considered in medication dosages, such as age, weight, gender and ethnicity. Some of that is already being done in infants. But right now it’s not one of the factors considered in adults, scientists say, and more work needs to be done before such consideration is warranted.

“Low birth weight affects the development of organs, as the fetus tries to finish development of the brain and, in a sense, sacrifice as necessary the ordinary development of organs such as the kidney,” said Ganesh Cherala, an assistant professor in the OSU/OHSU College of Pharmacy. “But the kidney is one of the primary filtering agents in the body, and is directly involved in drug elimination.”

According to Dr. Cherala, the kidneys of low birth weight individuals have a significantly impaired ability to filter and excrete foreign compounds. Since the biologic impact of a medication is affected by its absorption, metabolism and excretion, low birth weight individuals might be less able to excrete drugs.

However, because of liver metabolism and other issues, in many cases low birth weight individuals end up having less response to a drug, instead of more.

Cherala: “A pain killer, for instance, might end up being metabolized in the liver instead of making its way to the brain where it is supposed to function. You might need more of that same drug in a low birth weight individual to have the same effect.”

The complexities of these processes need additional study before recommendations could be made to alter drug dosages based on low birth weight status, Cherala said. But this issue could be important and should be further explored, he said.

In developed countries about 8-10 percent of individuals are born with low birth weight, but the issue is of higher concern in some developing nations where 20-25 percent of babies are born with this condition.

Low birth weight is generally caused by poor nutrition during pregnancy.

Perinatal growth restriction programs higher risk for chronic disease during adulthood via morphological and physiological changes in organ systems. Perinatal growth restriction is highly correlated with a decreased nephron number, altered renal function and subsequent hypertension. We hypothesize that such renal maladaptations result in altered pharmacologic patterns for life. Maternal protein restriction during gestation and lactation was used to induce perinatal growth restriction in the current study. The diuretic response of furosemide (2 mg/kg single i.p. dose) in perinatally growth restricted rats during adulthood was investigated. Diuresis, natriuresis and renal excretion of furosemide were significantly reduced relative to controls, indicative of decreased efficacy. While a modest 12% decrease in diuresis was observed in males, females experienced 26% reduction. It is important to note that the baseline urine output and natriuresis were similar between treatment groups. The in vitro renal and hepatic metabolism of furosemide, the in vivo urinary excretion of the metabolite, and the expression of renal drug transporters were unaltered. Creatinine clearance was significantly reduced by 15% and 19% in perinatally growth restricted male and female rats, respectively. Further evidence of renal insufficiency was suggested by decreased uric acid clearance. Renal protein expression of sodium–potassium–chloride cotransporter, a pharmacodynamic target, was unaltered. In summary, perinatal growth restriction could permanently imprint pharmacokinetic processes affecting drug response.

Fetal programming; Furosemide; In utero growth restriction; Perinatal growth restriction; Pharmacokinetics; Renal insufficiency

Corresponding author contact information
Corresponding author at: Department of Pharmacy Practice, College of Pharmacy, Oregon State University/Oregon Health & Science University, 3303, SW Bond Avenue, CH12C, Portland, OR 97239, USA. Tel.: +1 503 418 0447;fax: +1 503 494 8797.

About the OSU College of Pharmacy: The College of Pharmacy prepares students of today to be the pharmacy practitioners and pharmaceutical sciences researchers of tomorrow by contributing to improved health, advancing patient care and the discovery and understanding of medicines.