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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
CLICK ON weeks 0 - 40 and follow along every 2 weeks of fetal development


Low birth weight babies near coal-fired power plant

From 1990 through 2006 about 25% of mothers living as far as 20 to 30 miles from a notorious power plant known to give off sulfur dioxide, delivered babies below 6 pounds.

A study of live births occurring from 1990 to 2006 in the area downwind of an infamous Pennsylvania power plant, is the first study to explore the impact of a specific known polluter on prenatal health.

The U.S. Environmental Protection Agency (EPA) studied the effects of coal-fired power plant emissions on premature mortality, nonfatal heart attacks, hospital and emergency room visits, acute bronchitis, upper and lower respiratory symptoms, aggravated asthma, and lost work days or school absences. However, this new study details benefits to fetal health.

The study is published in the Journal of Policy Analysis and Management appearing online now.

"A robust association has been found in the literature between birth weight and outcomes during adulthood, such as health, educational attainment, and earnings."

Muzhe Yang PhD, Associate Professor, Department of Economics, College of Business and Economics, Lehigh University, Bethlehem, Pennsylvania USA.

In the United States, emissions that cross state borders complicate regulation of power plants. Each state has the authority to regulate plants within its own boundaries, but regulating upwind and downwind states is a problem.

The study examines a unique power plant located on the border between two states. The Portland Generating Station of Pennsylvania power plant has polluted downwind New Jersey for years with spill-over scientifically proven by New Jersey and by the federal government. Two petitions were filed by the New Jersey Department of Environmental Protection (NJDEP) with the EPA, showing sulfur dioxide (SO2) emissions from the plant reached four New Jersey counties 20 to 30 miles away.

Infants born to mothers living as far as 20—30 miles downwind from the power plant were 6.5% more likely to be born below 2,500 grams or 5.5 pounds; and 17.12% more likely to be born below 1,500 grams or 3.3 pounds.

According to a 2007 Environmental Integrity Project report, Portland Generating Station is ranked #5 among the 50 "dirtiest"  US power plants due to its sulfur dioxide emission rate. The first of two NJDEP's petitions showed 30,465 tons of sulfur dioxide were emitted by the plant in 2009 alone, more than double the sulfur dioxide emissions from all power-generating facilities in New Jersey combined.

The EPA eventually ruled against the plant. It is now rebuilding to suit more restrictive emission guidelines.

To examine the infant health impact of prenatal exposure to power plant emissions, we draw scientific evidence on the impacted region downwind of a large polluter, a coal-fired power plant located on the border of two states and proven to be the sole contributor to the violation of air quality standards of the impacted region. Our results show that among all live singleton births that occurred during 1990 through 2006, those born to mothers living as far as 20 to 30 miles away downwind from the power plant (which is also an affluent region) during pregnancy are at greater risks of low birth weight (LBW) and very low birth weight (VLBW): the likelihoods of LBW and VLBW could increase approximately by 6.50 and 17.12 percent, respectively. In light of the continual efforts of The U.S. Environmental Protection Agency in reducing cross-state air pollution caused by transboundary power plant emissions, our study is aimed at broadening the scope of cross-border pollution impact analysis by taking into account adverse infant health effects of upwind polluters, which can impose disproportionate burdens of health risks on downwind states due to air pollutants transported by wind.

Other Authors
Co-authors include Shin-Yi Chou, Professor of Economics at Lehigh University; Rhea A. Bhatta, Data Analyst at the Department of Pathology and Laboratory Medicine, University of Pennsylvania; and, Cheng-I Hsieh, Associate Professor at the Department of Bioenvironmental Systems Engineering, National Taiwan University.

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Apr 11, 2017   Fetal Timeline   Maternal Timeline   News   News Archive   

Coal Fired Plant in Ghana
Image Credit: Ghana Youth Environmental Movement


Phospholid by Wikipedia