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Herbal use before and during pregnancy

Published:December 28, 2009DOI:https://doi.org/10.1016/j.ajog.2009.10.865

      Objective

      We estimated the prevalence and patterns of herbal use among US women before and during pregnancy.

      Study Design

      The National Birth Defects Prevention Study is an ongoing, population-based, case-control study. This analysis included 4239 women from 10 centers in the United States who delivered infants without major birth defects from 1998–2004.

      Results

      The prevalence of reported herbal use 3 months before or during pregnancy was 10.9%. During pregnancy, prevalence was 9.4% and was highest in the first trimester. Higher prevalence was associated with age greater than 30 years and education greater than 12 years. Use varied considerably by state (5–17%). Ginger and ephedra were the most commonly reported products early in pregnancy; teas and chamomile were most commonly reported throughout pregnancy.

      Conclusion

      Potentially 395,000 US births annually involve antenatal exposure to herbal products. Health care providers should inquire routinely about herbal use and educate patients about what little is known regarding risks of these products.

      Key words

      According to the 2002 National Health Interview Survey, an estimated 38 million US adults per year use herbal therapies.
      • Gardiner P.
      • Kemper K.J.
      • Legedza A.
      • Phillips R.S.
      Factors associated with herb and dietary supplement use by young adults in the United States.
      The reported prevalence of herbal use is higher among women than among men.
      • Gardiner P.
      • Kemper K.J.
      • Legedza A.
      • Phillips R.S.
      Factors associated with herb and dietary supplement use by young adults in the United States.
      There is a lack of published US data on the frequency of herbal use among women of childbearing age in general; published estimates specifically during pregnancy range from 4.1–45.2%, but these were based on sample sizes of only 150–734 women.
      • Hepner D.L.
      • Harnett M.
      • Segal S.
      • Camann W.
      • Bader A.M.
      • Tsen L.C.
      Herbal medicine use in parturients.
      • Refuerzo J.S.
      • Blackwell S.C.
      • Sokol R.J.
      • et al.
      Use of over-the-counter medications and herbal remedies in pregnancy.
      • Tsui B.
      • Dennehy C.E.
      • Tsourounis C.
      A survey of dietary supplement use during pregnancy at an academic medical center.
      • Glover D.D.
      • Amonkar M.
      • Rybeck B.F.
      • Tracy T.S.
      Prescription, over-the-counter, and herbal medicine use in a rural, obstetric population.
      Studies have shown that many patients do not disclose use of herbals to their health care providers; estimates of nondisclosure range from 25–58%.
      • Gardiner P.
      • Kemper K.J.
      • Legedza A.
      • Phillips R.S.
      Factors associated with herb and dietary supplement use by young adults in the United States.
      • Tsui B.
      • Dennehy C.E.
      • Tsourounis C.
      A survey of dietary supplement use during pregnancy at an academic medical center.
      • Eisenberg D.M.
      • Davis R.B.
      • Ettner S.L.
      • et al.
      Trends in alternative medicine use in the United States, 1990-1997: results of a follow-up national survey.
      • Leung J.M.
      • Dzankic S.
      • Manku K.
      • Yuan S.
      The prevalence and predictors of the use of alternative medicine in presurgical patients in five California hospitals.
      • Howell L.
      • Kochhar K.
      • Saywell Jr, R.
      • et al.
      Use of herbal remedies by Hispanic patients: do they inform their physician?.
      For Editors' Commentary, see Table of Contents
      Under the Dietary Supplement Health and Education Act of 1994, the responsibility for ensuring safety before marketing rests with the manufacturers, and the US Food and Drug Administration (FDA) can take regulatory action only if it can prove that a product is unsafe once it reaches the market.
      US Food and Drug Administration Center for Food Safety and Applied Nutrition
      Dietary Supplement Health and Education Act (DSHEA) of 2004.
      Therefore, in contrast to prescription and newer over-the-counter medications, herbal products usually are marketed without the benefit of clinical trials to demonstrate either efficacy or safety.
      Safety concerns related to herbal products have emerged. These safety concerns have been attributed to the herbal ingredient itself (eg, ephedra and kava),
      • Rados C.
      Ephedra ban: no shortage of reasons.
      National Institutes of Health Office of Dietary Supplements
      Botanical dietary supplements: background information Dietary supplement fact sheet.
      interactions between a herbal product and other pharmaceuticals (eg, Ginkgo biloba and blood-thinning agents, ginseng, and insulin),
      • Dugoua J.J.
      • Mills E.
      • Perri D.
      • Koren G.
      Safety and efficacy of ginkgo (Ginkgo biloba) during pregnancy and lactation.
      • Vickers A.
      • Zollman C.
      ABC of complementary medicine: herbal medicine.
      and contamination of products by unlabeled toxins (eg, lead and mercury).
      • Saper R.B.
      • Kales S.N.
      • Paquin J.
      • et al.
      Heavy metal content of ayurvedic herbal medicine products.
      • Ko R.J.
      Adulterants in Asian patent medicines.
      Herbal use surrounding pregnancy raises particular concerns, because many herbals are marketed specifically for symptoms that occur commonly during pregnancy, such as nausea and vomiting.
      • Allaire A.D.
      • Moos M.K.
      • Wells S.R.
      Complementary and alternative medicine in pregnancy: a survey of North Carolina certified nurse-midwives.
      More importantly, our ignorance of the potential harm to the pregnant woman is complicated by our even greater ignorance of the potential effects on fetal safety.
      Because little is known about the extent of herbal use among pregnant women, we estimated the prevalence and pattern of use among women immediately before and during pregnancy.

      Materials and Methods

      To estimate the prevalence of herbal use among a population-based sample of women who delivered liveborn infants with no major birth defects, we used data from the National Birth Defects Prevention Study (NBDPS). The NBDPS is an ongoing, population-based, case-control study involving case infants with major structural birth defects and control infants without such defects, conducted in 10 centers across the United States: Arkansas, California, Georgia, Iowa, Massachusetts, New Jersey, New York, North Carolina, Texas, and Utah. Each center defined a study region with between 35,000–75,000 births per year, which in some cases was statewide and in other cases was a region in a state.
      The control infants are a random sample of live births drawn from the same source population as the case infants, with the selection occurring from either birth certificates or hospital birth records. About 900 mothers of control infants are interviewed each year, and only control mothers were included in this analysis. The study was approved by the institutional review boards of the Centers for Disease Control and Prevention and all participating study centers.
      The study uses a computer-assisted telephone interview to collect data from mothers about exposures in the 3 months before pregnancy and throughout pregnancy, the latter defined as the time period from conception (ie, 2 weeks after the last menstrual period) to delivery. Each month was a 30-day period, and, for this analysis, trimesters were defined as 3-month periods (first trimester: pregnancy months 1–3; second trimester: pregnancy months 4–6; and third trimester: pregnancy months 7–9, which some mothers did not reach, because they delivered in the second trimester). Interviews are conducted from 6 weeks to 2 years after the estimated date of delivery (EDD), with a mean and median time to interview for control mothers of 8.9 and 7.7 months, respectively, after the EDD.
      The questionnaire item related to herbal use stated: “Did you use any herbs or folk medicines to treat any medical conditions, to lose weight, or just to keep you healthy?” This question covered the time period from 3 months before pregnancy to the date of the child's birth. Analysis was restricted to control mothers who had answered this particular question.
      From among the responses provided by study participants, herbal products in this analysis were defined as “products containing a plant, plant part, or plant extract (excluding topicals)” (eg, black cohosh, chamomile oil, ephedra, and Ginkgo biloba). Products were classified using the Slone Drug Dictionary from Boston University's Slone Epidemiology Center,
      • Kelley K.
      • Kelley T.
      • Kaufman D.
      • Mitchell A.
      The Slone Drug Dictionary: a research driven pharmacoepidemiology tool.
      which links the reported substances to their active ingredients. We included herbal teas that were reported in response to the specific herbal question or in any other section of the questionnaire.
      When herbal exposure was reported in an alternate section of the questionnaire (eg, vitamin use section or maternal illness section), the reason for use was attributed to that topic. We excluded exposure to single herbals in mainly vitamin-dominated multivitamin supplements.
      The herbal question was added in mid-2000; therefore, for this analysis, we included only women interviewed after this time, which corresponds to participants with EDDs between mid-1998 and the end of 2004 (4239/5958 total controls). The participation rate in the maternal interview was approximately 69% among control mothers for this time period.
      STATA 8 software (Stata Corp, College Station, TX) was used for all analyses. We cross-tabulated herbal use with each sociodemographic characteristic of interest to determine the prevalence associated with each of these factors. The 3 months prior to pregnancy and the 3 trimesters of pregnancy were each considered a distinct “period” for purposes of this analysis, and prevalence of herbal use was calculated for each of the 4 periods. Percentages of mothers taking each herbal product were tabulated and ranked to determine the most commonly reported herbals.

      Results

      Overall, 462 (10.9%) of the 4239 control mothers reported use of any herbal product in the 3 months before pregnancy or during pregnancy. The prevalence of herbal use by state varied considerably, with the lowest use in Iowa and North Carolina (5.4% and 6.1%, respectively) and the highest in Utah (16.5%) (Table 1). Use increased with age and also was greatest among women with more than a high school education and among women with a household income of $20,000 or more per year. Hispanics reported the highest prevalence of herbal use of all racial or ethnic groups studied.
      TABLE 1Sociodemographic characteristics of control mothers by reported herbal use 3 months before and during pregnancy, 1998–2004
      Maternal characteristicReported herbal product use, n (%)No reported herbal product use, nOdds ratio95% confidence interval
      Maternal age at delivery, y
       <2039 (8.8)4041.0Referent
       20–2488 (8.8)9071.00.7–1.5
       25–29120 (10.7)9991.30.9–1.8
       30–34141 (13.0)9461.51.1–2.2
       35–3962 (12.4)4401.51.0–2.2
       ≥4012 (12.9)811.50.8–3.1
      Maternal education, y
       <1268 (9.2)6711.20.9–1.7
       12 (high school)80 (7.7)9541.0Referent
       >12310 (12.7)21261.71.3–2.3
      Household income
       <$20K114 (8.8)11811.0Referent
       ≥$20K330 (12.3)23511.51.2–1.8
      Study site
       Arkansas50 (9.2)4930.70.5–1.1
       California75 (13.1)4991.10.7–1.5
       Georgia53 (12.5)3721.0Referent
       Iowa24 (5.4)4190.40.2–0.7
       Massachusetts66 (12.1)4801.00.7–1.4
       New Jersey33 (10.3)2860.80.5–1.3
       New York40 (12.1)2901.00.6–1.5
       North Carolina18 (6.1)2760.50.3–0.8
       Texas60 (11.9)4440.90.6–1.4
       Utah43 (16.5)2181.40.9–2.1
      Maternal race or ethnicity
       Non-Hispanic white260 (10.5)22081.0Referent
       Non-Hispanic black46 (9.8)4250.90.7–1.3
       Hispanic123 (12.5)8631.21.0–1.5
       Other33 (11.1)2641.10.7–1.6
      Maternal body mass index, kg/m2
       Underweight (<18.5)17 (7.2)2180.60.4–1.0
       Normal (18.5 to <25)260 (11.6)19791.0Referent
       Overweight (25 to <30)98 (10.6)8250.90.7–1.2
       Obese (≥30)67 (10.1)5970.90.6–1.1
      Maternal smoking in first trimester
      Included 1 month before pregnancy and first trimester;
       Smoked77 (9.8)7100.90.7–1.1
       Did not smoke384 (11.2)30521.0Referent
      Year of estimated date of delivery
       1998–2000115 (12.1)8391.20.9–1.6
       200182 (10.3)7111.00.7–1.4
       200275 (10.6)6311.10.8–1.5
       200399 (11.1)7911.10.8–1.5
       200491 (10.2)8051.0Referent
      Time to interview
      Time to interview could not be calculated for 1 control subject because of a missing interview date.
       <6 mo159 (11.9)11831.0Referent
       6 to <12 mo203 (11.0)16350.90.7–1.2
       12 to <18 mo77 (10.8)6350.90.7–1.2
       >18 mo22 (6.7)3060.50.3–0.9
      Broussard. Herbal use before and during pregnancy. Am J Obstet Gynecol 2010.
      a Included 1 month before pregnancy and first trimester;
      b Time to interview could not be calculated for 1 control subject because of a missing interview date.
      In the 3 months before pregnancy, the overall prevalence of herbal use was 5.7%. Only 65 mothers reported herbal exposure limited to the 3 months before pregnancy (ie, none were exposed during pregnancy); therefore, the overall prevalence of herbal use anytime during pregnancy was 9.4%.
      During pregnancy, the prevalence was highest (6.9%) during the first trimester, but a substantial proportion of women took herbals during the latter trimesters as well (5.1% and 5.2% during the second and third trimesters, respectively); 275 (6.5%) mothers were exposed during more than 1 of the 4 periods, and 87 (2.1%) mothers were exposed in all 4 periods.
      Timing of pregnancy recognition was available for all but 2 participants included in the analysis. Of these 4237 pregnancies, 52% were recognized by the mother during the first month, 37% during the second month, and 12% during the third month or beyond. Herbal use was significantly higher after pregnancy recognition (7.6% vs 6.1%; P = .003).
      Among reported products, the most common herbals (each taken by <3% of mothers) were herbal teas, ephedra and ephedra-containing products (which also tended to include ginger, ginseng, or both), chamomile, echinacea, and ginger (Table 2). The other common products (reported by <0.5% of mothers) were cranberry extract, raspberry leaf, mint or peppermint, and primrose oil. A total of 33 of 119 herbal tea users also took another type of herbal product. Excluding the 86 women who used herbal teas only, the prevalence of all other herbal products used 3 months before or during pregnancy was 8.9%.
      TABLE 2Top reported herbals used in the 3 months before and during pregnancy among control mothers, 1998–2004
      Herbal productAny use, n (%)
      Any use is defined as any reported use from 3 months before pregnancy through the end of pregnancy;
      Use ≤3 months before pregnancy, n (%)Use during pregnancy, n (%)First trimester use, n (%)Second trimester use, n (%)Third trimester use, n (%)
      n = 4239, except for the third-trimester denominator, which excluded 14 women who delivered during the second trimester (n = 4225).
      Herbal teas119 (2.8)51 (1.2)109 (2.6)77 (1.8)66 (1.6)75 (1.8)
      Ephedra49 (1.2)48 (1.1)25 (0.6)25 (0.6)1 (0.0)0 (0.0)
      Chamomile43 (1.0)20 (0.5)42 (1.0)29 (0.7)31 (0.7)27 (0.6)
      Echinacea40 (0.9)30 (0.7)25 (0.6)19 (0.4)14 (0.3)7 (0.2)
      Ginger24 (0.6)3 (0.1)24 (0.6)22 (0.5)10 (0.2)6 (0.1)
      Broussard. Herbal use before and during pregnancy. Am J Obstet Gynecol 2010.
      a Any use is defined as any reported use from 3 months before pregnancy through the end of pregnancy;
      b n = 4239, except for the third-trimester denominator, which excluded 14 women who delivered during the second trimester (n = 4225).
      Distribution of use of these most common products differed somewhat by trimester. As shown in Table 2, ginger was used predominantly during the first trimester, likely because of its claim to prevent nausea and vomiting during pregnancy. Ephedra was used both before pregnancy and during the first trimester of pregnancy (but not later in pregnancy); in contrast, herbal teas and chamomile were used throughout all 4 periods of pregnancy.
      Although there appeared to be no substantial differences in the use of herbal teas, echinacea, or ginger by year of EDD (Figure), the prevalence of ephedra use declined substantially from 2002–2004, and chamomile use was reported more commonly by women with EDDs in the years 1998–2000.
      Figure thumbnail gr1
      FIGURETime period for top reported herbal use 3 months before and during pregnancy
      Because the herbal question was added in 2000 but time intervals from EDD to interview varied, we created a time period of 1998–2000 to provide a similar number of participants as the single-year periods for comparison; 1998–2000, n = 954; 2001, n = 793; 2002, n = 706; 2003, n = 890; 2004, n = 896.
      EDD, estimated date of delivery.
      Broussard. Herbal use before and during pregnancy. Am J Obstet Gynecol 2010.
      Reported reasons for herbal use often were nonspecific, because they generally were attributed to the topic section of the questionnaire in which the herbal was reported. The most common reasons given for use, corresponding to topic areas in the interview, were as remedies or vitamins, and for respiratory conditions, morning sickness, and urinary tract infections. Of note, a considerable proportion (approximately 40% of the multiple-component products or 9% of all products) of the herbals had intended uses that included weight loss or body enhancement.

      Comment

      If we assume that our control mothers were representative of the 4.2 million births each year in the United States,
      • Hamilton B.E.
      • Martin J.A.
      • Ventura S.J.
      Births: preliminary data for 2006.
      our findings project that 9.4%, or an estimated 395,000 such births, will involve antenatal exposure to at least 1 herbal product. Furthermore, the fact that use of herbal products was greatest during the first trimester raises concerns about fetal safety, because this is a critical period of fetal organ development.
      • Cunningham F.G.
      • Gant N.F.
      • Leveno K.J.
      • Gilstrap L.C.
      • Hauth J.C.
      • Wenstrom K.D.
      Fetal growth and development. Williams obstetrics.
      Of note, in April 2004, the FDA withdrew ephedra from the market because of concerns about cardiovascular effects, such as increased blood pressure and irregular heart rhythm among adults
      • Rados C.
      Ephedra ban: no shortage of reasons.
      (which could have implications for fetal risk); our survey documented that use declined subsequent to that withdrawal, but even with that decline, we estimated that there were 21,000–71,400 ephedra-exposed births per year over the course of the study period.
      Slone Survey data restricted to women of childbearing age (18–44 years) found an approximate 10% prevalence of herbal use during the period 1998–2000 and about 15% use during the period 2001–2002.
      • Kelly J.P.
      • Kaufman D.W.
      • Kelley K.
      • Rosenberg L.
      • Anderson T.E.
      • Mitchell A.A.
      Recent trends in use of herbal and other natural products.
      Among the few studies that have considered herbal use among pregnant women, Tsui et al
      • Tsui B.
      • Dennehy C.E.
      • Tsourounis C.
      A survey of dietary supplement use during pregnancy at an academic medical center.
      reported a prevalence of 20% before pregnancy and 13% during pregnancy, and a recent Quebec study reported 15.4% used herbals in the year before pregnancy and 9% used herbals during pregnancy,
      • Moussally K.
      • Oraichi D.
      • Berard A.
      Herbal products use during pregnancy: prevalence and predictors.
      although that study had some methodologic limitations.
      One US study and 1 Swedish study also found an association of herbal use with advanced maternal education.
      • Refuerzo J.S.
      • Blackwell S.C.
      • Sokol R.J.
      • et al.
      Use of over-the-counter medications and herbal remedies in pregnancy.
      • Holst L.
      • Nordeng H.
      • Haavik S.
      Use of herbal drugs during early pregnancy in relation to maternal characteristics and pregnancy outcome.
      An Australian study found, as we did, that herbal use was highest during the first trimester compared with immediately before pregnancy or during the subsequent 2 trimesters.
      • Maats F.H.
      • Crowther C.A.
      Patterns of vitamin, mineral and herbal supplement use prior to and during pregnancy.
      This study was subject to several limitations. The self-reported exposure assessment, combined with the variable time to interview, might have led to exposure misclassification or a lack of specificity in defining the mother's herbal exposure, particularly because the herbal interview question was open ended. Because one-fifth of control mothers were interviewed 12–24 months after the EDD, these interviews relied on women's recall of exposures up to 3 years in the past.
      There has thus far been no consensus on how best to ascertain herbal use in population surveys. In the NBDPS,
      • Yoon P.W.
      • Rasmussen S.A.
      • Lynberg M.C.
      • et al.
      The National Birth Defects Prevention Study.
      the Behavioral Risk Factor Surveillance System,
      • Holtzman D.
      The behavioral risk factor surveillance system.
      the National Health and Nutrition Examination Survey,
      Centers for Disease Control and Prevention
      National Health and Nutrition Examination Survey Questionnaire, 1999-2000.
      the Infant Feeding Practices Study,
      • Fein S.B.
      • Labiner-Wolfe J.
      • Shealy K.R.
      • Li R.
      • Chen J.
      • Grummer-Strawn L.M.
      Infant Feeding Practices Study II: study methods.
      the Boston University Slone Epidemiology Center's Birth Defects Study,
      • Werler M.M.
      • Mitchell A.A.
      • Hernandez-Diaz S.
      • Honein M.A.
      Use of over-the-counter medications during pregnancy.
      and the Slone Survey,
      • Kaufman D.W.
      • Kelly J.P.
      • Rosenberg L.
      • Anderson T.E.
      • Mitchell A.A.
      Recent patterns of medication use in the ambulatory adult population of the United States: the Slone survey.
      each has taken a slightly different approach to questioning participants about herbal use.
      A workshop held as part of the planning for the National Children's Study summarized some of the approaches used in previous studies.
      National Children's Study Workshop
      Use of herbal products in pregnancy, breastfeeding, and childhood.
      It has been shown that ascertainment of medication exposure improves with the specificity of the question,
      • Mitchell A.A.
      • Cottler L.B.
      • Shapiro S.
      Effect of questionnaire design on recall of drug exposure in pregnancy.
      and it is reasonable to extrapolate this observation to herbals.
      Visual aids have been particularly helpful, specifically for identification of herbals. Because no pictures or examples of herbals were provided in our study, it is possible that herbal use might have been overreported or underreported.
      Furthermore, unlike prescription and over-the-counter medications, the ingredients in herbal products cannot reliably be predicted from the user's description of the product or even brand name because, due to the nature of the herbal product industry, proprietary blends can change, and labeled ingredients might be inaccurate.
      • Harris I.M.
      Regulatory and ethical issues with dietary supplements.
      Our estimates are conservative in that we excluded from our definition of herbals those multivitamin products that might contain a single herbal component.
      A previous analysis comparing demographic and health factors of NBDPS control infants with those from natality data of target populations found the control participants to be generally representative of their base populations, particularly in terms of maternal and paternal age, previous live births, maternal smoking, and maternal diabetes.
      • Cogswell M.
      • Bitsko R.
      • Anderka M.
      • et al.
      Control selection and participation in an ongoing, population-based, case-control study of birth defects, the National Birth Defects Prevention Study.
      This study also showed that the extent to which these controls were representative of the general population might be affected by the selection method, which differed by study center (hospital-based or birth certificate-based control selection).
      In conclusion, we found that use of herbal products during the period just before and during pregnancy was relatively common among US women. Because of remarkably limited knowledge regarding the effects of herbals on the developing fetus, it is critical that we focus attention on the study of the risks and relative safety of herbal products in pregnancy. As more data accumulate, the NBDPS will attempt to evaluate the fetal risks and safety of herbal products taken by pregnant women, including the effects of specific herbal products on selected birth defects and interactions between herbals and over-the-counter and prescription medications.
      In the meantime, health care providers should recognize that, despite the widespread use of herbal products by women of childbearing age, many herbal users do not disclose their use to a medical professional.
      • Gardiner P.
      • Kemper K.J.
      • Legedza A.
      • Phillips R.S.
      Factors associated with herb and dietary supplement use by young adults in the United States.
      • Tsui B.
      • Dennehy C.E.
      • Tsourounis C.
      A survey of dietary supplement use during pregnancy at an academic medical center.
      • Eisenberg D.M.
      • Davis R.B.
      • Ettner S.L.
      • et al.
      Trends in alternative medicine use in the United States, 1990-1997: results of a follow-up national survey.
      • Leung J.M.
      • Dzankic S.
      • Manku K.
      • Yuan S.
      The prevalence and predictors of the use of alternative medicine in presurgical patients in five California hospitals.
      • Howell L.
      • Kochhar K.
      • Saywell Jr, R.
      • et al.
      Use of herbal remedies by Hispanic patients: do they inform their physician?.
      Providers should therefore attempt, in a routine and nonjudgmental fashion, to query patients about their use of herbals, and to counsel them that the fact that a substance is natural does not necessarily mean that it is safe for the fetus.
      • Friedman J.M.
      Teratology Society: presentation to the FDA public meeting on safety issues associated with the use of dietary supplements during pregnancy.
      Providers also should inform patients that it would be prudent to err on the side of caution regarding use of these products during and surrounding pregnancy, because little is known about their potential risks.

      Acknowledgments

      Coding of drug information in the NBDPS used the Slone Drug Dictionary, under license from the Slone Epidemiology Center at Boston University, Boston, MA. We wish to thank the study participants, interviewers, and collaborators at all of the Centers for Birth Defects Research and Prevention: University of Arkansas for Medical Sciences, Little Rock, AK (Charlotte Hobbs, MD; U50/CCU613236); California March of Dimes, Oakland, CA (Gary Shaw, DrPH; U50/CCU913241); University of Iowa, Iowa City, IA (Paul Romitti, PhD; U50/CCU713238); Massachusetts Department of Public Health, Boston, MA (Marlene Anderka, PhD; U50/CCU113247); New York State Department of Health, Albany, NY (Charlotte Druschel, MD; U50/CCU223184); University of North Carolina School of Public Health, Chapel Hill, NC (Andrew Olshan, PhD; Robert Meyer, PhD; U50/CCU422096); Texas Department of State Health Services, Austin, TX (Mark Canfield, PhD; Peter Langlois, PhD; U50/CCU613232); Utah Department of Health, Salt Lake City, UT (Marcia Feldkamp, PhD, PA, MSPH; U50/CCU822097).

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