According to the CDC, about 600,000 American women ages 15-44 have high blood lead levels, putting them and their children at risk for adverse health outcomes.
To address this heightened risk, the CDC has released new guidelines(www.cdc.gov) to help physicians identify lead exposure in and manage the care of pregnant and lactating women who have been exposed to the hazardous material. The guidelines also address management strategies for infants exposed to lead in utero.
According to Crystal Cash, M.D., chair of the department of family and community medicine for the Cook County Health and Hospital Systems in Chicago and the AAFP's representative to the CDC workgroup on lead and pregnancy that created the guidelines, the take-home message for physicians is to identify pregnant women who are at risk.
"Providers of care for pregnant women need to be aware that there are certain at-risk populations that need to be screened, especially if they find that a child in the home has lead poisoning," said Cash, who also is professor of clinical medicine at Loyola University's Stritch School of Medicine in Maywood, Ill., "Then, more than likely, the whole family is at risk for lead exposure."
The following groups are at increased risk for lead exposure, according to the CDC:
- recent immigrants from areas with high lead levels in the environment;
- women who work with lead;
- certain racial and ethnic groups; and
- women who practice pica (i.e., eating nonfood items such as pottery, clay and dirt).
"(Lead exposure) tends to be more of a problem in areas that have heavy immigrant populations," Cash said in an interview with AAFP News Now. "If you're in an area that has a large Central and South American population, and you're finding elevated lead (levels) in children, you should be checking the pregnant women."
Women and children also can be exposed to lead during renovations of older homes.
Mary Jean Brown, R.N., Sc.D., chief of the Healthy Homes and Lead Poisoning and Prevention Branch of the CDCs' National Center for Environmental Health, said during an interview(www2c.cdc.gov) posted on the agency's website that state and local public health officials should identify populations at risk and share that information with physicians to guide them in determining the need for population-based blood lead testing.
The CDC guidelines will be reviewed by the AAFP's Commission on Health of the Public and Science. In 2006, the Academy endorsed the U.S. Preventive Services Task Force, or USPSTF, recommendation against routine screening of pregnant women for elevated blood lead levels(www.uspreventiveservicestaskforce.org). At that time, however, the USPSTF acknowledged that certain groups of women were at increased risk for lead exposure, including those who
- have a low income,
- live in an urban residence,
- have low educational attainment,
- use ethnic remedies,
- use certain cosmetics,
- have exposure to lead-glazed pottery,
- use alcohol, and
Brown said that physicians and their pregnant patients should discuss each woman's potential for lead exposure. She also said assessment for exposure based on risk-factor questionnaires or blood level testing should take place during a physician's earliest contact with a pregnant woman.
The USPSTF recommendations also call for the use of screening questionnaires and stress that such documents should be tailored and validated for clinical use in specific communities.
According to the CDC guidelines, blood lead levels of 5 micrograms per deciliter, or 5mcg/dL, or higher in pregnant women indicate previous or ongoing lead exposure.
If a pregnant woman has been exposed to lead, Brown said physicians should work with their local health department to identify and remove the source of exposure, ensuring that the woman and her infant go home to a lead-free environment.
The workgroup found evidence that fetal lead exposure impairs neurodevelopment -- leaving children at risk for developmental delays, reduced IQ and behavior problems -- and leads to a variety of health problems later in life, including high blood pressure. However, Brown said children exposed to lead in the womb but not after birth fare better than those exposed before and after birth.
Physicians also should assess the patient's diet and provide nutritional advice, she said.
According to Brown, if blood lead levels reach 45 mcg/dL or higher during a woman's pregnancy or a child's early infancy, chelation may be warranted. However, she cautioned that this step should be taken only after consultation with an expert in chelation for lead poisoning.
Finally, the CDC recommendations state that lactating mothers should pump and discard their breast milk until their blood lead level falls to less than 40 mcg/dL before starting to breastfeed their infants.
The guidelines, which were six years in the making, fill more than 300 pages. However, Cash said that time-strapped physicians can benefit from reading the key points and recommendations that are listed at the beginning of each chapter.
"It's not as daunting as you might think just by looking at it," she noted.