(NaturalNews) Between 200,000 and 300,000 hip replacement operations are performed each year in the U.S., mostly in people over the age of 60. However, according to the American Academy of Orthopaedic Surgeons (AAOS), five to 10% of these procedures are in patients younger than 50 -- including women of childbearing age. Now comes a disturbing report that suggests women who have the metal-on-metal type of artificial hip joint and become pregnant could be putting their unborn babies at risk.
A study by researchers at Rush University Medical Center recently presented at the 2010 Annual Meeting of the American Academy of Orthopaedic Surgeons held in New Orleans revealed that expectant mothers with metal-on-metal hip implants pass metal ions to their offspring during pregnancy. The ions, it turns out, result from wear and tear as well as from corrosion as the parts of the artificial joint, called prosthesis, rub against one another.
Dr. Joshua Jacobs, professor and chairman of orthopedic surgery at Rush University Medical Center, and his research team investigated three women who had metal-on-metal hip implants and gave birth two to six years after their surgeries. Blood samples from the mothers as well as umbilical cord blood samples were obtained at the time of delivery and tested for blood serum concentrations of titanium, nickel, cobalt and chromium. The researchers used inductively coupled plasma mass spectrometry, a highly sensitive technique that can detect even minute amounts of metals in biological samples.
The results showed that the moms with metal-on-metal implants and their babies had significantly higher levels of two metals -- chromium and cobalt -- compared with a control group of seven women who did not have metal hip replacements and their offspring. In addition, the levels of the metals in the blood of mothers with implants correlated with the levels of metals identified in the umbilical cords.
The amount of cobalt found in the newborn babies was about half that in the mothers' blood; chromium was about 15 percent as high in the infants as the levels in their mothers' blood. The lower levels in the umbilical cords showed that the placenta stopped at least some of the transfer of metal ions from mother to fetus, although it was obviously not a complete barrier.
"We don't know whether metal ions pose any health risks for pregnant women and their babies but as metal-on-metal implants increase in popularity and use, especially among young, active patients, women of child-bearing age and their doctors need to be aware of these findings when considering options for hip replacements," Dr. Jacobs explained in a statement to the media.
While there's no absolute proof the metal ions are dangerous for moms or babies, previous research concerning these metals should raise some concern. For example, the Department of Health and Human Services (DHHS), the International Agency for Research on Cancer (IARC), and the EPA have all determined that chromium metal compounds are known human carcinogens. In addition, based on animal studies, the International Agency for Research on Cancer (IARC) has determined that cobalt and cobalt compounds could possibly cause cancer in humans.
Bottom line: women who plan on having children would be wise to consider natural and less invasive alternatives to metal hip replacement surgery. For example, keeping weight under control and appropriate exercise such as yoga can often help ease symptoms of osteoporosis, a condition that can lead to hip replacement surgery.