For several years, health workers have been trying to figure out why some communities in rural Washington seem to be having babies with a higher incidence rate of rare and fatal birth defects. A recent government report found that cases are still climbing and scientists are actually no closer to figuring out the cause.

The Centers for Disease Control and Prevention reviewed pregnancies in three counties in central Washington from January 2010 to January 2013, identifing 27 pregnancies affect by some sort of neural tube defect, mostly anencephaly, which is a condition when the neural tube fails to close and the baby is born without parts of the brain and skull.

There were 23 incidents of anencephaly, three cases of spina bifida and one case of encephalocele in Yakima, Benton and Franklin counties during this time frame. In 2013, after the review period, seven cases of anencephaly were reported in these counties.

This incident rate in Washington for anencephaly is four times the national average.

Image source: CDC

Image source: CDC

Juliet VanEenwyk, an epidemiologist with the Washington State Department of Health, told Reuters that an initial investigation a couple years ago did not give any clear indication of what could be causing these higher rates of anencephaly. The most common risk factors associated with this birth defect, like being an obese mother, were not correlated with what’s going on in Washington, according to Reuters.

The lower than national average rate for spina bifida, a normally non-fatal defect where the neural tube does not close completely, added to health researcher’s confusion.

“That’s one of the things that’s really strange about this,” VanEenwyk said, speaking at a public Q&A meeting in the state Tuesday.

Babies anencephaly have several brain and skull defects because their neural tube failed to close. Cases of anencephaly are fatal. (Image source: CDC)

Babies anencephaly have several brain and skull defects because their neural tube failed to close. Cases of anencephaly are fatal. (Image source: CDC)

“We would love to find a smoking gun, and have things align; if you find a cause, you can prevent. If you can’t find a cause, you can’t prevent,” VanEenwyk said at the event, according to the Yakima Herald-Republic.

One woman at Tuesday’s meeting was pregnant with a child who has anencephaly. She is carrying the pregnancy to term to “cherish the few minutes” she can get with the baby before it will die.

“I’m going to see my baby at least for a little bit,” the mother-to-be said.

Watch this report from KOMO-TV about the clusters of these birth defects:

Previous studies have shown that a diet that includes folic acid, a compound in many leafy greens and other foods, can help prevent such neural tube defects. The CDC recommends women — not just pregnant women but all who are child-bearing age — consume at least 400 mcg of folic acid daily. Many vitamins contain the recommended amount of folic acid and most cereals are fortified with vitamins that can give people their daily dose as well.

VanEenwyk noted that in the three counties, 60 percent of pregnant women were not taking folic acid as a supplement, though it didn’t seem to be higher for those women with children born with these defects, according to Reuters.

Possible causes that have been investigated include nitrates in the water, ethnicity, pesticide exposure and obesity, none of which turned up anything truly significant at the time. According to the Herald-Republic, scientists think it is probably many factors. Hispanic women, an ethnicity that makes up much of the population in these counties, have a higher incidence rate of these defects genetically. This coupled with the possibility of not taking enough folic acid could contribute to this unusual cluster in the state.

State health officials are reconvening in June to address how to move forward with the anencephaly incidents investigation in Washington.

Front page image via ML Cohen/Flickr.