Toxins and Pregnancy
You're finally pregnant – and the world seems fraught with dangers. Here's a guide to help you navigate through the legitimate concerns and the baseless worries.
The Big Gray Area
According to ACOG, there is "limited evidence of varying degrees to
document teratogenicity" for a number of agents -- some of which may
Linda R. Chambliss, MD, MPH, spokeswoman at ACOG, explains that the lack of
conclusive data on such agents is due to research constraints.
"The best research requires randomized studies in which you have a group
of people exposed to a substance and a control group that's not exposed.
Researchers are loathe to put pregnant women into randomized studies [exposing
some to potential toxins], so they rely on animal studies or on women reporting
what they were exposed to during pregnancy," she says.
Chambliss, a professor of obstetrics and gynecology at St. Louis School of
Medicine in Missouri, talks to WebMD about her advice on some of the most
common "gray area" substances:
"You do not want [to take] aspirin or other nonsteroidal
anti-inflammatory drugs (NSAIDs), such as Advil or Motrin. They can affect
platelet count and bleeding time, and have been associated with fetal defects.
I would advise a pregnant woman to avoid these unless they're prescribed by a
physician." Acetaminophen, or Tylenol, should be taken instead of aspirin,
Advil, or Motrin for fever, headache, minor aches, and pains.
"There's little data on newer antihistamines. The older ones work by
causing vasoconstriction [constriction of blood vessels], so there's some
concern about using them in the first trimester." Examples of
antihistamines include Claritin, Zyrtec, Allegra, and Benadryl.
"not a lot of information".
"ACOG and the American Academy of Pediatrics say that moderate use,
about a couple of cups per day, does not increase reproductive risk. Many
people who use caffeine also smoke and drink alcohol, so it's hard to tease out
caffeine. Is it the smoking, caffeine, alcohol? Or do they work
synergistically? It's not clear."
Occupational chemical agents:
"Fertilizers might pose a problem for agricultural workers, but for
occasional residential use, you don't have to leave your house when your lawn
gets fertilized. Working in an office where you use Wite-Out or permanent
markers is not a concern, but tell your physician about occupational exposures
in industrial or agricultural environments. A lot of obstetricians don't think
to ask about occupational exposure."
"If a woman continued taking oral contraceptives because she didn't know
she was pregnant, I would tell her to stop. There have been some problems in
terms of birth defects. The doctor will take a look at possible interactions
and perhaps use an ultrasound to look at the fetus. What has been reported is a
less than 1% risk of masculinization of the female fetus."
"If you have your house sprayed for bugs routinely, I'd be concerned;
but if it's a one-time exposure, use common sense. Pesticides have real risks,
but most of the data involves agricultural workers."