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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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Chemicals from fracking may harm fertility

More than 15 million Americans live within one-mile of Unconventional Oil and Gas (UOG) operations. UOGs combine directional drilling and hydraulic fracturing, or "fracking," to release natural gas from underground rock. Now, exposure to fracking and drilling chemicals, even at the lowest doses, are found to alter the ovaries of mice.

Although ongoing scientific studies are still evaluating the potential long-term effects of hydraulic fracturing on human development, research from the University of Missouri is the first to link exposure to chemicals released during hydraulic fracturing to adverse reproduction and development in mice. The work is published in the journal of Endocrinology.

Scientists believe that exposure to fracking chemicals could thus pose a threat
to human development.

According to Susan C. Nagel, associate professor of obstetrics, gynecology and women's health at the University of Missouri School of Medicine, previous research has found that endocrine-disrupting chemicals (EDCs) mimic or block hormones which regulate respiration, reproduction, metabolism, growth and other biological functions in animals. This new study adds that exposure during fetal development to these chemicals poses a threat to future fertility in animals and by extension, to humans. Mice exposed to the lowest doses of chemicals, lower that what is found in groundwater from spills and wastewater, had low fertility as adults.

Researchers mixed 23 oil and gas chemicals at four different concentrations to reflect the chemical combinations found in drinking water and groundwater at fracking sites. These mixtures were added to drinking water fed to pregnant laboratory mice until they gave birth, in order to measure any affects on their pups.

The results show that female mouse pups of mothers drinking fracking water, when compared to female mouse pups in a control group not exposed, had lower levels of reproductive hormones.

"These findings build on our previous research, which found exposure to the same chemicals was tied to reduced sperm counts in male mice.

"Our studies suggest adverse development and reproductive health might be expected in humans and animals exposed to chemicals in regions with oil and gas drilling activity."

Susan C. Nagel PhD, Associate Professor, Obstetrics, gynecology and Women's Health, School of Medicine, University of Missouri; Adjunct Associate Professor, Biological Sciences, University of Missouri, College of Arts and Science.

Unconventional oil and gas operations using hydraulic fracturing can contaminate surface and groundwater with endocrine-disrupting chemicals. We have previously shown that 23 of 24 commonly used hydraulic fracturing chemicals can activate or inhibit the estrogen, androgen, glucocorticoid, progesterone, and/or thyroid receptors in a human endometrial cancer cell reporter gene assay and that mixtures can behave synergistically, additively, or antagonistically on these receptors. In the current study, pregnant female C57Bl/6 dams were exposed to a mixture of 23 commonly used unconventional oil and gas chemicals at approximately 3, 30, 300, and 3000 μg/kg·d, flutamide at 50 mg/kg·d, or a 0.2% ethanol control vehicle via their drinking water from gestational day 11 through birth. This prenatal exposure to oil and gas operation chemicals suppressed pituitary hormone concentrations across experimental groups (prolactin, LH, FSH, and others), increased body weights, altered uterine and ovary weights, increased heart weights and collagen deposition, disrupted folliculogenesis, and other adverse health effects. This work suggests potential adverse developmental and reproductive health outcomes in humans and animals exposed to these oil and gas operation chemicals, with adverse outcomes observed even in the lowest dose group tested, equivalent to concentrations reported in drinking water sources. These endpoints suggest potential impacts on fertility, as previously observed in the male siblings, which require careful assessment in future studies. - See more at: http://press.endocrine.org/doi/abs/10.1210/en.2016-1242#sthash.5IEGnFLH.dpuf

Authors of the study include: Christopher D. Kassotis of Duke University in Durham, N.C.; John J. Bromfield of the University of Florida in Gainesville, FL; Kara C. Klemp, Chun-Xia Meng, Victoria D. Balise and Chiamaka J. Isiguzo of the University of Missouri; Andrew Wolfe of the Johns Hopkins University School of Medicine in Baltimore, MD; R. Thomas Zoeller of the University of Massachusetts Amherst in Amherst, MA; and Donald E. Tillitt of the U.S. Geological Survey's Columbia Environmental Research Center in Columbia, MO.

The research was funded by the University of Missouri Research Council and Mizzou Advantage, a crowd-funding campaign on Experiment.com, and the U.S. Environmental Protection Agency's STAR Fellowship Assistance Agreement awarded to Christopher D. Kassotis. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies.
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Sep 5, 2016   Fetal Timeline   Maternal Timeline   News   News Archive   

Fracking involves drilling into shale layers deep underground and injecting large amounts of water
mixed with sand and a brew of toxic chemicals under high pressure to release natural gas.
In recent years, the industry has begun horizontal fracking to extend the wells, sometimes for miles.
Image Credit:Appalation Voices



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