Investigation and Outreach

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What problem is under investigation?

Why was the investigation started?

What did the investigation find?

What are the latest anencephaly data from central Washington?

What is the Department doing to promote folic acid access and use?

What problem was under investigation?

The Washington State Department of Health investigated the occurrence and possible risk factors for neural tube defects in Yakima, Benton and Franklin counties from 2010-2017. Neural tube defects are major birth defects of a baby's brain and spine, including anencephaly and spina bifida. These conditions occur early in pregnancy, often before a woman realizes she is pregnant. Spina bifida can cause physical and cognitive disabilities that range from mild to severe depending on the degree that the spinal cord is affected. Anencephaly, the condition our investigation focused on, is always fatal. Many infants are stillborn and others die within hours or days after delivery.

Why was the investigation started?

A health care provider in central Washington reported an unusual number of infants born with anencephaly. After verifying the concern through hospital records, we joined local public health agencies and partnered with the Centers for Disease Control and Prevention (CDC) to investigate neural tube defects, including spina bifida and anencephaly. The initial investigation included a medical records review of all pregnancies in the area affected with neural tube birth defects. The department compared this to information from randomly selected pregnancies without birth defects. No differences were found between the affected and unaffected pregnancies.

Increases of unusual health conditions like this are concerning and difficult to investigate. Several factors can increase the risk for neural tube defects. Among these factors are low folic acid intake, maternal diabetes, obesity, some medications, Hispanic ethnicity, and having a previous neural tube defect-affected pregnancy.

What did the investigation find?

As part of the investigation, we conducted a medical records based study comparing neural tube defect-affected pregnancies with unaffected pregnancies from 2010-2013. We also did descriptive epidemiology and surveillance of neural tube defects, including the exploration of potential exposures to radiation, pesticides and nitrates in drinking water, and interviewed women with affected pregnancies. Unfortunately, we did not find a preventable cause for most of the neural tube defect-affected pregnancies.

We did learn, however, that women in the three-county area have low folic acid use in early pregnancy compared to women in the rest of Washington. Folic acid, a B vitamin, is important for a baby's very early development and has been shown to reduce a woman's risk of having a neural tube defect-affected pregnancy.

While we have ended our formal investigation, we are continuing to work to prevent neural tube defects throughout Washington by promoting folic acid use by all women of reproductive age, and partnering to increase women's access to folic acid. It is important that all women of reproductive age take folic acid because the neural tube is formed very early in pregnancy, often before a woman knows she is pregnant.

What are the anencephaly data from central Washington?

Anencephaly by Year of Delivery or Estimated Year of Delivery1 in Benton,
Franklin and Yakima Counties

Year1 Number Total births Rate per 10,000 95% Confidence Interval
2010 6 8565 7.0 (2.6, 15.2)
2011 4 8528 4.7 (1.3, 12.0)
2012 9 8352 10.8 (4.9, 20.5)
2013 9 8084 11.1 (5.1, 21.1)
2014 8 8432 9.5 (4.1, 18.7)
2015 5 8332 6.0 (2.0, 14.0)
2016 2 8330 2.4 (0.3, 8.7)
20172 4 7934 5.0 (1.4, 12.9)
Total to date3 47 66557 7.1 (5.2, 9.4)

1 Estimated year of delivery is used for cases terminated or delivered before 37 weeks gestation.

2 Total births for 2017 are preliminary as of April 24, 2018.

3 Total reflects cases confirmed by January 23, 2018 with a delivery date or estimated date of delivery in 2010-2017.

What is the Department doing to promote folic acid access and use?

The Department continues to work with partners to raise awareness about the importance of folic acid to all women of reproductive age. This work includes efforts to get free prenatal vitamins for women, and integrating messages about folic acid into our family planning, women's health, WIC nutrition, and parenting programs. We post this information on our website, and have also modified radio novellas that raise awareness about healthy habits for women of child bearing age to reduce birth defects. The radio novellas are available in English (Love and Health) and Spanish (Amor y Salud). The WIC program provides vouchers for foods that are high in folate and Medicaid pays for folic acid supplements for women of child bearing age. We continue to work with the March of Dimes and other partners to explore innovative ways to reach all women of reproductive age.

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