New study links high levels of cadmium, lead in blood to pregnancy delay
Higher blood levels of cadmium in females, and higher blood levels of lead in males, delayed pregnancy in couples trying to become pregnant, according to a study by researchers at the National Institutes of Health and other academic research institutions.
Cigarette smoke is the most common source of exposure to cadmium,, a toxic metal found in the earth's crust, which is used in batteries, pigments, metal coatings and plastics. Smokers are estimated to have twice the levels of cadmium as do non-smokers. Exposure also occurs in workplaces where cadmium-containing products are made, and from the air near industrial facilities that emit cadmium. Airborne cadmium particles can travel long distances before settling on the ground or water. Soil levels of cadmium vary with location. Fish, plants, and animals absorb cadmium from the environment, and all foods contain at least low levels of the metal.
Lead, a toxic metal also found in the earth's crust, is used in a variety of products, such as ceramics, pipes, and batteries. Common sources of lead exposure in the United States include lead-based paint in older homes, lead-glazed pottery, contaminated soil, and contaminated drinking water.
Exposure to these metals is known to have a number of effects on human health, but the effects on human fertility have not been extensively studied, especially when studying both partners of a couple.
The study was published online in Chemosphere. The study's principal investigator was Germaine M. Buck Louis, Ph.D., director of the Division of Epidemiology, Statistics, and Prevention Research at the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). Other authors of the study were from the NICHD, the Texas A&M Health Science Center School of Rural Public Health, College Station; The Ohio State University College of Medicine, Columbus; The EMMES Corp. in Rockville, Md.; the National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta; and the Rollins School of Public Health at Emory University, Atlanta.
"Our results indicate that men and women planning to have children should minimize their exposure to lead and cadmium," Dr. Buck Louis said. "They can reduce cadmium exposure by avoiding cigarettes or by quitting if they are current smokers, especially if they intend to become pregnant in the future. Similarly, they can take steps to reduce their exposure to lead based paints, which may occur in older housing, including during periods of home renovation."
To conduct the study, the researchers enrolled 501 couples from four counties in Michigan and 12 counties in Texas, from 2005 to 2009. The women ranged from 18 to 44 years of age, and the men were over 18. Couples provided blood samples for the analysis of three heavy metals. Women kept journals to record their monthly menstrual cycles and the results of home pregnancy tests. The couples were followed until pregnancy or for up to one year of trying.
The researchers ranked the study participants on the basis of their blood levels of lead and cadmium. The researchers also measured the participants' blood mercury levels, but found they were not associated with the length of time couples required to become pregnant. Nearly every study participant had some exposure to these common metals, although blood levels of the metals varied across participants.
Researchers calculated the probability that a couple would achieve pregnancy by levels of blood cadmium and lead with a statistical measure called the fecundability odds ratio. The measure estimates couples' probability of pregnancy each cycle, by their blood concentration of metals. A ratio less than one suggests a longer time to pregnancy, while a ratio greater than one suggests a shorter time to pregnancy. Females' blood cadmium concentration was associated with a ratio below 1 (0.78), which means that the probability of pregnancy was reduced by 22 percent with each increase in the level of cadmium. Males' blood lead exposure also was associated with a ratio below 1 (0.85) with increasing levels, or about a 15 percent reduction in the probability of pregnancy for each increase in the level of blood lead concentrations.
The researchers also calculated a fecundability odds ratio based on both partners' combined lead, cadmium and mercury concentrations. The researchers found a ratio of 0.82 for male lead exposure, representing approximately a 28 percent reduction in the probability of pregnancy for each menstrual cycle, with increasing male blood lead concentration.
"The findings highlight the importance of assessing couples' exposure jointly, in a single, combined measure," Dr. Buck Louis said. "Males matter, because couples' chances of becoming pregnant each cycle were reduced with increasing blood lead concentrations in men."
Provided by National Institutes of Health
- Association between elevated levels of lead, cadmium and delayed puberty in girls Sep 02, 2010 | not rated yet | 0
- Low level cadmium exposure linked to lung disease Aug 19, 2008 | not rated yet | 0
- Cadmium investigated as cause of endometrial cancer Jun 09, 2010 | not rated yet | 0
- Researchers investigate links between prostate, cadmium, zinc Jan 30, 2008 | not rated yet | 0
- Wal-Mart still selling Miley Cyrus cadmium jewelry May 19, 2010 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
Classical and Quantum Mechanics via Lie algebras
Apr 15, 2011 I'd like to open a discussion thread for version 2 of the draft of my book ''Classical and Quantum Mechanics via Lie algebras'', available online at http://lanl.arxiv.org/abs/0810.1019 , and for the...
- More from Physics Forums - Independent Research
More news stories
Authorities are investigating rice mills in southern China following tests that found almost half of the staple grain in one of the country's largest cities was contaminated with a toxic metal.
Health 2 hours ago | 5 / 5 (1) | 0
The warning images Brussels proposes to include on tobacco packages in order to reduce consumption do not make the desired impact on smokers because they only find some of them really unpleasant. So, if the ...
Health 3 hours ago | not rated yet | 0
Ten years after the Iraq war of 2003 a team of scientists based in Mosul, northern Iraq, have detected high levels of uranium contamination in soil samples at three sites in the province of Nineveh which, coupled with dramatically ...
Health 3 hours ago | not rated yet | 0
When it comes to men's sexual health, dirty jokes may just be the best medicine. A QUT researcher is helping Family Planning Queensland (FPQ) use comedy and YouTube to deliver sexuality education to young ...
Health 4 hours ago | not rated yet | 0
(Medical Xpress)—International researchers are studying the salt intake of Indian adults to provide vital new data to aid the development of a national salt reduction strategy.
Health 5 hours ago | not rated yet | 0
(Medical Xpress)—Native peoples in regions where cameras are uncommon sometimes react with caution when their picture is taken. The fear that something must have been stolen from them to create the photo ...
42 minutes ago | not rated yet | 0 |
Australian scientists have charted the path of insulin action in cells in precise detail like never before. This provides a comprehensive blueprint for understanding what goes wrong in diabetes.
29 minutes ago | 4 / 5 (1) | 0 |
The level of immunity to the recently circulating H7N9 influenza virus in an urban and rural population in Vietnam is very low, according to the first population level study to examine human immunity to the virus, which was ...
8 minutes ago | not rated yet | 0 |
Researchers at Emory University have identified a protein that stimulates a pair of "orphan receptors" found in the brain, solving a long-standing biological puzzle and possibly leading to future treatments for neurological ...
4 minutes ago | not rated yet | 0 |
In a striking, unexpected discovery, researchers at Albert Einstein College of Medicine of Yeshiva University have determined that vitamin C kills drug-resistant tuberculosis (TB) bacteria in laboratory culture. The finding ...
20 minutes ago | not rated yet | 0 |
Prostaglandin analogues (PGAs), drugs which lower intraocular pressure, are often the first line of treatment for people with glaucoma, but their use is not without risks. PGAs have long been associated with blurred vision, ...
7 minutes ago | not rated yet | 0