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Are Women with Recent Live Births Aware of the Benefits of Folic Acid?

Indu B. Ahluwalia, M.P.H., Ph.D.
Division of Reproductive Health
National Center for Chronic Disease Prevention and Health Promotion

Katherine Lyon Daniel, Ph.D.
National Center on Birth Defects and Developmental Disabilities

Summary

Each year, approximately 4,000 pregnancies result in spina bifida or anencephaly, serious and often fatal conditions for the newborn. The B vitamin folic acid can reduce the incidence of these conditions by 50%--70%. To examine folic acid awareness among women who had recently delivered a live-born infant, CDC analyzed Pregnancy Risk Assessment Monitoring System (PRAMS) data for 1995--1998. The question used to measure awareness was, "Have you ever heard or read that taking the vitamin folic acid can help prevent some birth defects?" During the study period, overall folic acid awareness increased 15%, from 64% in 1996 to 73% in 1998, although changes varied by state. Despite this increase, differences in folic acid awareness were observed among different groups of women. Women who obtained a high school education or less; who were black, Hispanic, or from other racial/ethnic groups; who entered prenatal care after the first trimester; and whose pregnancies were unintended were less aware of folic acid.

This study indicates that gaps persist among women in low socioeconomic groups. Overall, PRAMS data indicated an increase in folic acid awareness among women with recent deliveries. However, this awareness might be too late for the pregnancy that has occurred, indicating a continued need to educate all reproductive-aged women regarding the need to take folic acid before they become pregnant.

BACKGROUND

Approximately 4,000 pregnancies are affected by neural tube birth defects each year in the United States (1). These conditions are serious defects in the formation of the brain and spine that are either fatal or have long-term health consequences. The formation of the neural tube occurs early in pregnancy --- in many cases, before a woman realizes she is pregnant and long before her first prenatal visit. Approximately 50% of neural tube defects are cases of anencephaly, in which the infant's brain is completely or partially missing, and these infants die before or shortly after birth. The other half of cases are spina bifida, which is a malformation of the spinal column that causes the spinal cord to form outside the protective backbone. Most children with spina bifida need numerous surgeries and experience problems throughout their lives, including paralysis, bowel or bladder incontinence, and learning disabilities. The social and economic costs of these conditions are high (2,3).

Research has demonstrated that periconceptional intake of 0.4 mg of the B vitamin folic acid reduces the risk for neural tube defects 50%--70% (4--8). Periconceptional multivitamin use can also reduce the risk for other defects (e.g., orofacial clefts, conotruncal heart defects, and urinary tract defects) (9--11). In response to the findings that folic acid can prevent neural tube defects, several national initiatives were implemented. In 1992, the U.S. Public Health Service (PHS) recommended that all women capable of becoming pregnant consume 0.4 mg of folic acid per day to reduce the risk for neural tube defects (12). In 1996, the U.S. Food and Drug Administration (FDA) mandated that all enriched cereal grain products be fortified with folic acid beginning in January 1998 (13). In April 1998, the Food and Nutrition Board of the National Academy of Sciences recommended that all women of reproductive age consume 400 micrograms of synthetic folic acid daily from supplements or fortified foods, in addition to folate found naturally in foods (14). Healthy People 2010 includes national objectives to increase folic acid consumption, increase red blood cell folate levels, and measure decreases in birth defects (15). Recent research has demonstrated that fortification and other health promotion efforts have caused a mean increase in blood folate levels among women of childbearing age (16--19). Given the association between folic acid consumption and reduction in neural tube defects and other birth defects, higher folate levels could reduce adverse birth outcomes in the United States (19,20). Many organizations and groups (e.g., CDC, March of Dimes) encourage clinicians and health-care providers to counsel reproductive-aged women regarding the need for periconceptional supplementation use to prevent neural tube defects (20--23). Despite these efforts, this information is apparently not getting to women of childbearing age quickly enough. An open-ended survey conducted by the Gallup Organization in 1998 for the national March of Dimes indicated that only approximately 13% of all women of childbearing age can spontaneously recall that folic acid can prevent birth defects, and even fewer (7%) know that folic acid must be consumed before pregnancy to provide this benefit (1,24,25). Based on surveys conducted in 1996 and 1997, the Behavioral Risk Factor Surveillance System (BRFSS) reported that approximately 35% of reproductive-aged women queried could correctly identify the purpose of folic acid from among four choices (26). The BRFSS is a state-based, random-digit--dialed telephone survey of the noninstitutionalized U.S. population aged >18 years.

This study sought to build on past research and promotion efforts by identifying changes and gaps in folic acid awareness among women who had recently delivered a live-born infant in the states that participate in the Pregnancy Risk Assessment Monitoring System (PRAMS). The specific research questions guiding this analysis were as follows:

  • Has there been a change in women's awareness regarding folic acid use?
  • How do the estimates of folic acid awareness among this population compare with estimates from national surveys (e.g., the March of Dimes survey and
  • BRFSS)?
  • Are there specific gaps that remain to be addressed in folic acid awareness among women who have recently given birth to a live-born infant and who are potentially at risk for future pregnancies, whether intended or unintended?

METHODS

Data

This study examined women's awareness regarding folic acid using data from PRAMS, which collects information on maternal behaviors and experiences during pregnancy from projects in 24 states* and New York City. Each month, PRAMS selects a stratified, systematic sample of 100--250 women who have recently given birth in a particular area from the birth certificates of the infants, and a survey questionnaire is mailed to the selected mothers approximately 2--6 months after delivery. Several attempts are made to contact the mother by mail. If that fails, the mother is contacted by telephone, and an attempt is made to interview her. The survey questionnaire is linked back to a select set of items from the birth certificate. The overall data are statistically weighted to adjust for the survey design, noncoverage, and nonresponse. Details of the methods and populations surveyed by PRAMS are provided elsewhere (27).

The current study used multiple years of data (1995--1998) from 13 states (n=58,625 births), with response rates ranging from 68% to >80%. Data from Alabama, Alaska, Arkansas, Colorado, Florida, Georgia, Maine, New York (excluding New York City), North Carolina, Oklahoma, South Carolina, Washington, and West Virginia were used. Because all of these states did not initiate data collection at the same time, earlier years of data did not exist for some states; for Georgia, no 1998 data were available. These states were chosen for analysis because they had the most years of data on folic acid awareness and adequate response rates to answer the research questions.

To define the measures used in this analysis, questions from the PRAMS survey and specific variables from birth certificates were used. The primary measure --- folic acid awareness --- was defined as women's responses to the following question: "Have you ever heard or read that taking the vitamin folic acid can help prevent some birth defects?" Response options were "yes" or "no." Reported race was classified as black, white, or other, and ethnicity was classified as either Hispanic or non-Hispanic. Education status was classified as less than high school, high school completion, or more than high school. Maternal age was divided into four categories (<19, 20--29, 30--39, and >40 years). Marital status was categorized as married or not married. Women who had >1 child were categorized as multipara, whereas those for whom the index birth was the first were categorized as primipara. Women who stated that they had insurance before they became pregnant were categorized as having insurance, and those who answered no were classified as not having any insurance before pregnancy. Women were asked what type of insurance paid for their prenatal care, with categories listed as Medicaid, private, and other. Enrollment in Medicaid or the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) was categorized as a dichotomous variable. Choices for place of prenatal care were hospital, health department, private doctor, Indian Health Service or other federally funded program, and other. In addition to demographic, health-care provider, and insurance variables, this study also examined women's pregnancy intention status, timing of prenatal-care initiation, and whether the prenatal-care provider discussed nutrition and the baby's growth and development. Women's pregnancy intentions were divided into four categories --- pregnancy was intended sooner, pregnancy was intended to occur at the time it did, pregnancy was intended for a later time, or pregnancy was not intended. Initiation of prenatal care was defined as entry into prenatal care during the first trimester or later/none. Women who had not obtained any prenatal care were put into the latter category. Whether women received professional advice on what to eat during pregnancy and whether their provider discussed fetal growth and development were defined as yes or no.

Software for Survey Data Analysis (SUDAAN) (Version 7.0; Research Triangle Institute, Research Triangle Park, North Carolina) was used for data analysis to ensure that the standard error estimates reflected the PRAMS survey design. Multiple logistic regression was used to examine overall gaps in folic acid awareness.

RESULTS

During 1995--1998, folic acid awareness increased overall and in most of the states in this analysis. The major shift appears to have occurred during 1996--1997 (Figure). Change in folic acid awareness is particularly noteworthy for the 10 states with data before 1997 (e.g., the percentage change in South Carolina was 27% during 1995--1998). However, not all states had large increases (e.g., the change in Washington was only 5% during 1996--1998), nor were all changes positive (Table 1). In 1998, the most recent year for which data were available, folic acid awareness ranged from 66.4% (95% confidence intervals [CI]=63.5%--69.3%) in Arkansas to 83.4% (95% CI=81.0%--85.7%) in Maine.

This study also examined folic acid awareness for 3 years (1996--1998), using certain demographic and prenatal-care characteristics, for all 13 states combined (Table 2). Prevalence estimates indicated an increase in folic acid awareness during 1996--1997 among all groups, although this increase appeared to level off during 1997--1998. Despite the overall increases, prevalence estimates remained lower among women who were younger; were not married; were black and Hispanic; had a high school education or less; were participating in WIC or received money from Medicaid for prenatal care; had no insurance before becoming pregnant; did not intend to become pregnant; began their prenatal care after the first trimester; and received prenatal care from the health department (Table 2).

The 1998 data were used to examine the correlates of folic acid awareness among women with recent live births. Multivariable analyses of these data indicated that women with a high school education or less and women who did not want to be pregnant at all were more than twice as likely to be unaware of the benefits of folic acid (Table 3). Compared with women who wanted their pregnancies to occur sooner, those who wanted their pregnancies then or later were also less likely to know about folic acid. Women who were black, Hispanic, or from other racial/ethnic groups, as well as those who entered prenatal care later than the first trimester or had no care and those whose providers did not discuss nutrition during prenatal visits were significantly less likely to be aware of the benefits of taking folic acid to prevent certain birth defects (Table 3). Women who were married and who reported that their place of prenatal care was the Indian Health Service or another federally funded program were more likely to know about folic acid.

DISCUSSION

PRAMS data indicate that women's awareness regarding folic acid use has increased since 1995--1996, with the level of increase varying by state. These findings suggest that health promotion efforts are working, albeit slowly in some populations, and that more women became aware of the benefits of folic acid during 1996--1998. Several national campaigns were implemented during the early to mid-1990s, including a March of Dimes campaign called Think Ahead in 1995. The Think Ahead campaign was designed to promote folic acid awareness through multiple channels (e.g., professional and public education, media campaigns, advertisements), and its efforts were supplemented by state initiatives designed to promote awareness and consumption of foods containing or fortified with folic acid (28). In 1997, the Florida Department of Citrus began to promote folic acid intake through consumption of orange juice, using paid television and radio advertisements, and this campaign was cited most often by 1998 focus group participants (29). PRAMS data also indicate that states with folic acid awareness data before 1996 reported a greater increase in awareness compared with those that did not. This finding suggests that national efforts coupled with state and local efforts to promote folic acid awareness could be contributing to this increase. In 1997, the National Council on Folic Acid (NCFA) was established to expand education efforts to both women and health professionals by working in partnership with local and state coalitions. NCFA consists of professional associations, maternal and child health advocacy groups, and community-based health organizations that have implemented education and folic acid awareness campaigns among their own memberships, as well as with reproductive-aged women (30). NCFA developed targeted messages for women intending pregnancy as well as for those capable of becoming pregnant who might not intend to become pregnant, given that 50% of pregnancies in the United States are unplanned (30,31). More information on NCFA is available on the Internet at <http://www.cdc.gov/ncbddd/folicacid/council/htm>.

PRAMS findings on folic acid awareness among women of childbearing age are similar to national estimates published by the March of Dimes from its 1998 survey of women aged 18--45 years. The March of Dimes reported that folic acid awareness increased from 52% in 1995 to 66% in 1997 to 68% in 1998 and to 75% in 2000 --- an overall increase of 44% (1,24,25). At the same time, consumption of vitamins containing folic acid increased from 28% in 1995 to 34% in 2000, a 22% increase (25). Although folic acid consumption behaviors lag behind knowledge/awareness, both behavior and knowledge have increased substantially among women aged 18--45 years, perhaps indicating that awareness is a precursor to voluntary behavior change (25). Although PRAMS estimates on awareness are slightly higher than those reported in the literature, they represent somewhat different populations. The PRAMS survey collects data from women who have recently given birth to a live-born infant, whereas the March of Dimes survey assessed awareness among women aged 18--45 years who are capable of becoming pregnant.

The format of the questions used by different surveys could also contribute to the differences observed in prevalence estimates. The March of Dimes survey used an open-ended format to collect information regarding folic acid knowledge/awareness. The PRAMS survey is intended to gauge general awareness, not a) whether respondents know how much folic acid to take, b) whether they know that they need folic acid before and during the earliest days of pregnancy, or c) when (i.e., before or during pregnancy) they became aware of the importance of taking folic acid. Another survey, the BRFSS survey, uses multiple choice questions that query reproductive-aged women regarding the purpose of folic acid. For 1996--1997, the BRFSS reported that approximately 35% of women recognized the "correct" answer from four options (26).

The analysis of PRAMS data also indicated that gaps in folic acid awareness exist among women who have had live births. Women from racial or ethnic minorities, who had attained a high school education or less, who received later or no prenatal care, and whose pregnancies were unintended were less likely to be aware of the benefits of folic acid. Other national studies have also reported gaps in folic acid awareness and consumption among low-income populations (25). One reason for these gaps could be that message dissemination within the health-care system is less likely to reach some women before pregnancy, and folic acid information must compete with many other health messages. Further research on the reasons for the gaps in folic acid awareness could offer opportunities to learn more regarding the effect of socioeconomic status (including available resources) on women's prepregnancy health and pregnancy intentions.

Data in this study indicated that no substantial differences in folic acid awareness existed among women of different age groups, parity, type of insurance, or WIC participation. Analysis also indicated that women whose health-care providers discussed nutrition during pregnancy were more likely to know the benefits of folic acid intake. Similarly, focus group research conducted by CDC reported that health professionals had more opportunity to discuss folic acid with women who were already pregnant (32). Although this education probably occurs too late to help many women prevent neural tube defects in their current pregnancy, the information could help them plan for future pregnancies. All reproductive-aged women, including uninsured women, should be provided the opportunity to discuss proper nutrition with their primary-care providers before conception.

In contrast to other studies, the research in this study is strengthened by its large, population-based sample from recent live births and its ability to identify gaps in women's awareness regarding the benefits of folic acid in preventing some birth defects. Although this study will be useful for promoting specific targeted efforts, several limitations exist. First, this research focuses on women's awareness, and no behavior data were available to assess folic acid consumption. Other studies of folic acid consumption have demonstrated a substantial gap between folic acid awareness and consumption behavior (25). Second, data from PRAMS could be biased because its surveys are administered after the birth of an infant, creating a time lapse since early pregnancy when women might have learned about folic acid. Third, the format of the PRAMS survey does not measure whether respondents know how much folic acid to take or that they need folic acid before and during the earliest days of pregnancy.

Although this study only assessed women's awareness of folic acid, other findings were reported. Some states had high rates of awareness overall, whereas others are lagging behind, and some populations are more disadvantaged than others. Healthy People 2010 objectives call for a 50% reduction in neural tube defect cases and an increase in daily consumption of 0.4 mg of folic acid from a baseline of 21% in the early 1990s to 80% by 2010 among nonpregnant women aged 15--44 years (Objectives 16-15 and 16-16) (15). Recent research indicates that red blood cell folate levels have increased among reproductive-age women (16--18), likely because of a) food fortification and b) increased folic acid awareness efforts coupled with some voluntary increase in folic acid consumption. Whether this increase has resulted in a reduction of neural tube defects is unknown because of the current status of research and the lag time in obtaining reliable data.

The results of this study could be used to promote healthier pregnancies by encouraging a) more prepregnancy planning, b) greater consumption of diets rich in vitamins (including folic acid) and minerals by women, and c) increased preconceptional health education for all women of reproductive age. Given the observed increase in women's awareness regarding folic acid over several years, particularly after the implementation of major national and state efforts, CDC recommends that health education efforts continue and expand on multipronged strategies to reach women in low socioeconomic and cultural groups. Specific messages and avenues of communication (e.g., media, interpersonal) for women in racial and ethnic groups should be identified and mobilized. In addition, health-care providers in general and prenatal-care providers in particular should take advantage of every preconceptional and early prenatal encounter to educate women and their families regarding pregnancy planning to ensure optimal pregnancy outcomes for women and infants. Also, comprehensive reproductive health policies that provide resources and opportunities for both men and women to make optimal preconceptional decisions should be implemented by health-care providers.

Acknowledgements

We are grateful for the contributions of the PRAMS working group, which includes the following states and collaborators: Albert Woolbright, Ph.D., Alabama; Kathy Perham-Hester, M.S., Alaska; Gina Redford, M.A.P., Arkansas; Darci Cherry, M.P.H., Colorado; Richard Hopkins, M.D., M.P.H., Florida; Tonya Johnson, Georgia; Barbara Yamashita, M.S.W., Hawaii; Bruce Steiner, M.A., Illinois; Susanne Straif-Bourgeois, Ph.D., M.P.H., Louisiana; Martha Henson, Maine; Donna Cheng, M.D., Maryland; Debbi Barnes-Josiah, Ph.D., Nebraska; Ssu Weng, M.D., New Mexico; Ann Radigan-Garcia, New York State; Fabienne Laraque, M.D., New York City; Paul Buescher, P.hD., North Carolina; Dick Lorenz, M.S., Oklahoma; Jo Bouchard, M.P.H., Ohio; Kristin Helms, M.S.P.H., South Carolina; Lois Bloebaum, Utah; Peggy Brozicevic, Vermont; Linda Lohdefinck, Washington; Melissa Baker, M.A., West Virginia; and the CDC PRAMS team.

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* Alabama, Alaska, Arkansas, Colorado, Delaware, Florida, Georgia, Hawaii, Illinois, Louisiana, Maine, Maryland, Mississippi, Nebraska, New Mexico, New York, North Carolina, Ohio, Oklahoma, South Carolina, Utah, Vermont, Washington, and West Virginia.


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