As many as 20 percent of infertile couples in the United States have unexplained reasons for their infertility. Now, new research led by Catherine Racowsky, PhD, director of the Assisted Reproductive Technologies Laboratory at Brigham and Women's Hospital (BWH), shows that exposure to BPA (Bisphenol-A) could be a contributing factor as to why some infertile couples are having difficulty conceiving. The study will be published online on July 31, 2013 in the journal Human Reproduction.
Images of eggs examined in this study show a properly formed spindle structure with aligned chromosomes (image A) and eggs with spindles of various abnormal shapes and misaligned chromosomes after being exposed to BPA (images B, C, D and E). The green images on the left are the eggs' spindle, the red center images are the eggs' chromosomes and the images on the right show the spindles and chromosomes merged together.
Credit: Brigham and Women's Hospital
"To our knowledge, this is the first study that has shown that BPA has a direct effect on egg maturation in humans," said Dr. Racowsky. "Because exposure to BPA is so ubiquitous, patients and medical professionals should be aware that BPA may cause a significant disruption to the fundamentals of the human reproductive process and may play a role in unexplained infertility."
The randomized trial examined 352 eggs from 121 consenting patients at a fertility clinic. The eggs, which would have otherwise been discarded, were exposed to varying levels (20 ng/ml, 200 ng/ml and 20 µg/ml) of BPA in a laboratory setting. An egg from each patient was not exposed to BPA and served as the control. Researchers then examined the eggs and found that exposure to BPA caused:
As the BPA dose increased, there was a decreased likelihood of maturity, an increased likelihood of degeneration and an increased likelihood of spontaneous activation. Additionally, among the mature eggs, there was a significant trend toward a decreased incidence of bipolar spindles and aligned chromosomes with an increased dose of BPA. Researchers note that these results are similar to the previous research examining the impact of BPA exposure on animal eggs.
Racowsky said, "Our data show that BPA exposure can dramatically inhibit egg maturation and adds to a growing body of evidence about the impact of BPA on human health. I would encourage further research to gain a greater understanding of the role BPA plays in infertility."
This study was funded by the NIEHS Center Grant Pilot Project (P30-ES000002). The full title of the paper is "Bisphenol-A and human oocyte maturation in vitro".
Tom Langford | EurekAlert!
New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)
Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...
23.05.2017 | Event News
22.05.2017 | Event News
17.05.2017 | Event News
23.05.2017 | Physics and Astronomy
23.05.2017 | Life Sciences
23.05.2017 | Medical Engineering