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Pregnancy Timeline by SemestersDevelopmental TimelineFertilizationFirst TrimesterSecond TrimesterThird TrimesterFirst Thin Layer of Skin AppearsEnd of Embryonic PeriodEnd of Embryonic PeriodFemale Reproductive SystemBeginning Cerebral HemispheresA Four Chambered HeartFirst Detectable Brain WavesThe Appearance of SomitesBasic Brain Structure in PlaceHeartbeat can be detectedHeartbeat can be detectedFinger and toe prints appearFinger and toe prints appearFetal sexual organs visibleBrown fat surrounds lymphatic systemBone marrow starts making blood cellsBone marrow starts making blood cellsInner Ear Bones HardenSensory brain waves begin to activateSensory brain waves begin to activateFetal liver is producing blood cellsBrain convolutions beginBrain convolutions beginImmune system beginningWhite fat begins to be madeHead may position into pelvisWhite fat begins to be madePeriod of rapid brain growthFull TermHead may position into pelvisImmune system beginningLungs begin to produce surfactant
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Developmental Biology - Fetal Toxins

PFCs in Food & Water Slow Fetal Growth

New method to identify PFCs in mother's blood which disrupt fetal development...

Fetal growth can be inhibited by a cocktail of chemicals found in mom. This is the first time researchers found how a combination of perfluorinated substances (PFCs) in mom significantly inhibit her child's growth.

The convenience these chemicals bring, such as keeping children's feet dry in waterproofed boots, stopping meat balls sticking to a frying pan and even making it easier to clean the carpet, come at the expense of our health. PFCs or perfluorinated substances, have a wide range of damaging effects — the most recent being reduced fetal growth.

A new study by researchers from Aarhus University in Denmark, examines the cocktail effect of these chemicals, showing results that are both significant and alarming.
"Perfluorinated (PFC) substances can mimic the hormone oestrogen and therefore disrupt the body's natural hormonal processes including the development of the fetus. We see that the complex mix of perfluorinated substances in the mother impairs her fetus in growth and length."

Professor Eva Cecilie Bonefeld-Joergensen PhD, Centre for Arctic Health and Molecular Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark; Greenland Center for Health Research, University of Greenland, Ilisimatusarfik, Nuuk, Greenland.

Previously,researchers had only studied individual impact of substances on a fetus, and the results had not been entirely clear-cut. But now, Eva Cecilie Bonefeld-Joergensen and her research colleagues have developed a new method for extracting and isolating substances from blood and can now determine the combined endocrine disrupting effect of these substances - popularly called the cocktail effect - on fetal development.
"When it comes to overall effect, the calculation isn't 1+1=2, but rather 1+1=3. Low birth weight can lead to a number of diseases later in life, but we still lack specific knowledge about how the children who are exposed to the substances subsequently develop."

Eva Cecilie Bonefeld-Joergensen PhD

Research results are published in the scientific journal Environmental Health Perspectives. Bonefeld-Joergensen is currently applying for a foundation grant to conduct follow-up studies on the ongoing development of children in her initial study.

Researchers examined blood samples from 702 pregnant Danish women registered in the "Aarhus Children's Biobank" database for this research. Such a thorough study of the concentration of perfluorinated substances and their biological affect on pregnant women had not been done previously. However, PFC substances have been associated with a range of issues including breast cancer, infertility, ADHD, risk for asthma, a weakened immune system and reducing the affect of vaccines.
Harmful environmental chemicals accumulated in the body are not easily degradable. They are fat and water repellent, found in our food, in the air we breathe, in dust and water and in a wide range of everyday products such as waterproof clothing, food packaging, furniture textiles and make-up. Only a few of the almost one thousand different PFCs are presently regulated by law, and there is no product labelling required.

Although the area is regulated by the European Union or EU, the Minister for Environment and Food, Jakob Ellemann-Jensen (of the Danish Liberal Party), has recently announced he will explore the possibility of banning PFCs in cardboard and paper used in food packaging. A new study, part of Aarhus University's Fetotox project, will broaden to include the impact of PFCs on all women and children.

Higher concentrations of single perfluorinated alkyl acids (PFAAs) have been associated with lower birth weight (BW), but few studies have examined the combined effects of PFAA mixtures. PFAAs have been reported to induce estrogen receptor (ER) transactivity, and estrogens may influence human fetal growth. We hypothesize that mixtures of PFAAs may affect human fetal growth by disrupting the ER.

We aimed to study the associations between the combined xenoestrogenic activity of PFAAs in pregnant women’s serum and offspring BW, length, and head circumference.

We extracted the actual mixture of PFAAs from the serum of 702 Danish pregnant women (gestational wk 11–13) enrolled in the Aarhus Birth Cohort (ABC) using solid phase extraction, high-performance liquid chromatography (HPLC), and weak anion exchange. PFAA-induced xenoestrogenic receptor transactivation (XER) was determined using the stable transfected MVLN cell line. Associations between XER and measures of fetal growth were estimated using multivariable linear regression with primary adjustment for maternal age, body mass index (BMI), educational level, smoking, and alcohol intake, and sensitivity analyses with additional adjustment for gestational age (GA) (linear and quadratic).

On average, an interquartile range (IQR) increase in XER was associated with a 48g48 g [95% confidence interval (CI): -90-90, -6-6] decrease in BW and a 0.3cm0.3 cm (95% CI: 0.1, 0.5) decrease in birth length. Upon additional adjustment for GA, the estimated mean differences were -28g-28g (95% CI: -60-60, 4) and -0.2cm-0.2cm (95% CI: -0.4-0.4, 0.0), respectively.

Higher-serum PFAA-induced xenoestrogenic activities were associated with lower BW and length in offspring, suggesting that PFAA mixtures may affect fetal growth by disrupting ER function. https://doi.org/10.1289/EHP1884

Christian Bjerregaard-Olesen, Cathrine Carlsen Bach, Manhai Long, Maria Wielsøe, Bodil Hammer Bech, Tine Brink Henriksen, Jørn Olsen and Eva Cecilie Bonefeld-Jørgensen.

We thank our fellow researchers of the FETOTOX project ( http://www.fetotox.au.dk) for their contributions to the work, especially technical assistant D. A. Dang for carrying out many of the ER transactivation assays and M. Ghisari for assisting with the serum extractions. We thank M. Pons providing the MVLN cell line.

The Danish Council supported the study for Strategic Research (Grant 10-092818). The funders were not involved in the research activities. The Aarhus Birth Cohort Biobank is funded by a grant from the Danish National Research Foundation with additional support from TrygFonden and the Aarhus University Research Foundation.

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Mar 11 2019   Fetal Timeline   Maternal Timeline   News  

Perfluorinated substances, such as the plastic wrap on these oranges and the tray they sit in, negatively impacts the fetus in pregnancy as well as our environment. Image: Stockholm University.

Phospholid by Wikipedia