Folic acid-containing supplement use among females aged 15-55 in the Canadian Community Health Survey 2015-2018

Folic acid-containing supplement use among females aged 15-55 in the Canadian Community Health Survey 2015-2018 | medRxiv /* */ /* */ <!-- <!-- /*! * yepnope1.5.4 * (c) WTFPL, GPLv2 */ (function(a,b,c){function d(a){return"[object Function]"==o.call(a)}function e(a){return"string"==typeof a}function f(){}function g(a){return!a||"loaded"==a||"complete"==a||"uninitialized"==a}function h(){var a=p.shift();q=1,a?a.t?m(function(){("c"==a.t?B.injectCss:B.injectJs)(a.s,0,a.a,a.x,a.e,1)},0):(a(),h()):q=0}function i(a,c,d,e,f,i,j){function k(b){if(!o&&g(l.readyState)&&(u.r=o=1,!q&&h(),l.onload=l.onreadystatechange=null,b)){"img"!=a&&m(function(){t.removeChild(l)},50);for(var d in y[c])y[c].hasOwnProperty(d)&&y[c][d].onload()}}var j=j||B.errorTimeout,l=b.createElement(a),o=0,r=0,u={t:d,s:c,e:f,a:i,x:j};1===y[c]&&(r=1,y[c]=[]),"object"==a?l.data=c:(l.src=c,l.type=a),l.width=l.height="0",l.onerror=l.onload=l.onreadystatechange=function(){k.call(this,r)},p.splice(e,0,u),"img"!=a&&(r||2===y[c]?(t.insertBefore(l,s?null:n),m(k,j)):y[c].push(l))}function j(a,b,c,d,f){return q=0,b=b||"j",e(a)?i("c"==b?v:u,a,b,this.i++,c,d,f):(p.splice(this.i++,0,a),1==p.length&&h()),this}function k(){var a=B;return a.loader={load:j,i:0},a}var l=b.documentElement,m=a.setTimeout,n=b.getElementsByTagName("script")[0],o={}.toString,p=[],q=0,r="MozAppearance"in l.style,s=r&&!!b.createRange().compareNode,t=s?l:n.parentNode,l=a.opera&&"[object Opera]"==o.call(a.opera),l=!!b.attachEvent&&!l,u=r?"object":l?"script":"img",v=l?"script":u,w=Array.isArray||function(a){return"[object Array]"==o.call(a)},x=[],y={},z={timeout:function(a,b){return b.length&&(a.timeout=b[0]),a}},A,B;B=function(a){function b(a){var a=a.split("!"),b=x.length,c=a.pop(),d=a.length,c={url:c,origUrl:c,prefixes:a},e,f,g;for(f=0;f<d;f++)g=a[f].split("="),(e=z[g.shift()])&&(c=e(c,g));for(f=0;f<b;f++)c=x[f](c);return c}function g(a,e,f,g,h){var i=b(a),j=i.autoCallback;i.url.split(".").pop().split("?").shift(),i.bypass||(e&&(e=d(e)?e:e[a]||e[g]||e[a.split("/").pop().split("?")[0]]),i.instead?i.instead(a,e,f,g,h):(y[i.url]?i.noexec=!0:y[i.url]=1,f.load(i.url,i.forceCSS||!i.forceJS&&"css"==i.url.split(".").pop().split("?").shift()?"c":c,i.noexec,i.attrs,i.timeout),(d(e)||d(j))&&f.load(function(){k(),e&&e(i.origUrl,h,g),j&&j(i.origUrl,h,g),y[i.url]=2})))}function h(a,b){function c(a,c){if(a){if(e(a))c||(j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}),g(a,j,b,0,h);else if(Object(a)===a)for(n in m=function(){var b=0,c;for(c in a)a.hasOwnProperty(c)&&b++;return b}(),a)a.hasOwnProperty(n)&&(!c&&!--m&&(d(j)?j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}:j[n]=function(a){return function(){var b=[].slice.call(arguments);a&&a.apply(this,b),l()}}(k[n])),g(a[n],j,b,n,h))}else!c&&l()}var h=!!a.test,i=a.load||a.both,j=a.callback||f,k=j,l=a.complete||f,m,n;c(h?a.yep:a.nope,!!i),i&&c(i)}var i,j,l=this.yepnope.loader;if(e(a))g(a,0,l,0);else if(w(a))for(i=0;i (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0];var j=d.createElement(s);var dl=l!='dataLayer'?'&l='+l:'';j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;j.type='text/javascript';j.async=true;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-P4HH5NV'); Skip to main content Home About Submit ALERTS / RSS Search for this keyword Advanced Search Folic acid-containing supplement use among females aged 15-55 in the Canadian Community Health Survey 2015-2018 View ORCID Profile Kathryn E. Hopperton , Lidia Loukine , The Minh Luong , Loan Nguyen , Jesse Bertinato , Yvette Bonvalot , Marcia Cooper , Wei Luo , Amanda J. MacFarlane , Jennifer McCrea , Carley Nicholson , Huma Rana , Kelsey Vercammen , Jane Yuan , Shawn Brule , Hope A. Weiler doi: https://doi.org/10.1101/2025.01.21.25320917 Kathryn E. Hopperton 1 Nutrition Research Division, Bureau of Nutritional Sciences, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Kathryn E. Hopperton For correspondence: Kathryn.hopperton{at}hc-sc.gc.ca Lidia Loukine 2 Bureau of Data, Science, and Knowledge Integration, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site The Minh Luong 2 Bureau of Data, Science, and Knowledge Integration, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Loan Nguyen 2 Bureau of Data, Science, and Knowledge Integration, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Jesse Bertinato 1 Nutrition Research Division, Bureau of Nutritional Sciences, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Yvette Bonvalot 2 Bureau of Data, Science, and Knowledge Integration, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Marcia Cooper 1 Nutrition Research Division, Bureau of Nutritional Sciences, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Wei Luo 3 Centre for Surveillance and Applied Research, Public Health Agency of Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Amanda J. MacFarlane 1 Nutrition Research Division, Bureau of Nutritional Sciences, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Jennifer McCrea 4 Bureau of Healthy Eating Policy and Promotion, Food and Nutrition Directorate , Health Products and Food Branch, Health Canada, Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Carley Nicholson 5 Maternal and Child Health Unit, Centre for Health Promotion, Public Health Agency of Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Huma Rana 4 Bureau of Healthy Eating Policy and Promotion, Food and Nutrition Directorate , Health Products and Food Branch, Health Canada, Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Kelsey Vercammen 3 Centre for Surveillance and Applied Research, Public Health Agency of Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Jane Yuan 6 Centre for Population Health Data , Statistics Canada, Ottawa, Ontario, Canada Find this author on Google Scholar Find this author on PubMed Search for this author on this site Shawn Brule 6 Centre for Population Health Data , Statistics Canada, Ottawa, Ontario, Canada Find this author on Google Scholar Find this author on PubMed Search for this author on this site Hope A. Weiler 1 Nutrition Research Division, Bureau of Nutritional Sciences, Food and Nutrition Directorate, Health Products and Food Branch , Health Canada , Ottawa, Ontario, Canada ; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Abstract Full Text Info/History Metrics Supplementary material Data/Code Preview PDF ABSTRACT Introduction In Canada, those who are or who could become pregnant are recommended to consume a daily multivitamin containing 400 µg of folic acid to help prevent neural tube defects. Objectives To report the prevalence and determinants of folic acid-containing supplement use among females of childbearing age in Canada. Methods Data were combined from cycles 2015/16 and 2017/18 of the maternal experiences module of the cross-sectional Canadian Community Health Survey, which was completed by females aged 15-55 years. Representative weighted estimates (means/percentages, 95% CI) were generated for folic acid-containing supplement use among all pregnant, non-pregnant, and lactating respondents. For those who had given birth in the preceding 5 years, estimates were also generated for supplement use in the 3 months before and first 3 months of their most recent pregnancy, and pre-pregnancy awareness of the link between folic acid and some birth defects. We examined associations with sociodemographic factors using multivariable logistic regression. Results Overall, 16.5% (15.9-17.0%) of non-pregnant, 80.3% (77.1-83.5%) of pregnant, and 58.4% (54.8-61.9%) of lactating females aged 15-55 reported using a folic acid-containing supplement. Among those who had given birth in the preceding 5 years, 63.7% ( 62.2-65.1%) consumed a folic acid-containing supplement in the 3 months prior to pregnancy, while 89.9% (88.8-90.9%) did so during the first trimester. Lower prevalence of supplement use before or during pregnancy was reported among the 23.7% (22.4-25.1%) of respondents unaware of the relationship between folic acid and birth defects. Younger age, single marital status, lower educational attainment, income below the median, and smoking were associated with lower odds of awareness or supplement use. Conclusion While most females living in Canada reported using folic-acid containing supplements prior to and during pregnancy, use of these supplements among non-pregnant females of childbearing age is low, and sociodemographic inequalities exist. INTRODUCTION Inadequate folate status in the periconceptional period is associated with a higher risk of neural tube defects (NTDs) among offspring ( 1 – 3 ). NTDs are a group of serious congenital conditions arising from incomplete closure of the neural tube between weeks 3 and 4 of gestation ( 4 ). Data from Canada and the United States suggests that 40-50% of pregnancies are unplanned, with a higher proportion of unplanned pregnancies among those in younger age groups ( 5 , 6 ). The folate status of those who could become pregnant is therefore a significant public health concern for the prevention of NTDs, whether a pregnancy is planned or not. To meet the needs of a diverse population, a multipronged approach to achieving adequate folate status as primary prevention of NTDs is likely necessary. Randomized controlled trials in the 1990s demonstrated substantial reductions in the risk of NTD occurrence and recurrence among participants randomized to consume a supplement containing folic acid in the period around conception ( 1 , 2 ). Based largely on these findings, many countries, including Canada and the United States, implemented mandatory fortification of the food supply with folic acid ( 3 , 7 ). Following the introduction of folic acid fortification in Canada in 1998, the prevalence of NTDs declined from 1.58 to 0.86 per 1000 births, a 46% reduction (95% CI: 40-51) ( 8 ). Other countries have seen similar declines in NTD prevalence following the introduction of fortification, with a 2019 meta-analysis of 8 studies and over 19 million births or still births reporting a 41% decrease (OR 0.59 [95% CI: 0.49-0.70]) ( 9 ). Despite this success, folic acid fortification alone is not sufficient to minimize population risk of NTDs. Nationally representative data from the 2015 Canadian Community Health Survey (CCHS) - Nutrition estimated that over 20% females of reproductive age have usual folate intakes below the estimated average requirement (EAR) from food sources alone ( 10 , 11 ). Complementing this, representative national biomonitoring data from cycle 1 of the Canadian Health Measures Survey (2007–2009) showed that 22% of females aged 15-45 had red blood cell folate concentrations <906 nmol/L, which is the level above which maximal NTD risk reduction is expected ( 12 ). Subsequent analyses have suggested that this may be an underestimation ( 13 ). Post-fortification data from the National Health and Nutrition Examination Survey (NHANES) suggests that a similar proportion of U.S women have suboptimal status (22.8% [95% CI: 21.1-24.6]) ( 14 ). Canadian public health agencies therefore recommend that anyone who could become pregnant consume a daily multivitamin containing 400 µg of folic acid, in addition to consuming a healthy diet that includes other sources of folate, to reduce their risk of a pregnancy affected by a NTD ( 4 , 15 ). Nationally representative data on folic acid-containing supplement use by females of childbearing age is collected annually in the CCHS, but the last published estimates are from 2006-7 post-censal Maternity Experiences Survey ( 16 – 18 ). The primary objective of our study was to provide updated estimates of the prevalence of folic acid-containing supplement use among pregnant and non-pregnant females aged 15-55 living in Canada, and of awareness of the link between folic acid and NTDs. Our secondary objective was to explore sociodemographic, geographic and health characteristics associated with supplement use that could help to tailor future public health initiatives within Canada and other countries with similar recommendations. We used two recent cycles of the CCHS (covering 2015-18) and examined folic acid-containing supplement use both among those who reported giving birth in the preceding 5 years, and among all females of childbearing age separated into groups of public health interest (non-pregnant, pregnant, and lactating). SUBJECTS AND METHODS The Canadian Community Health Survey Cycles 2015-2018 The CCHS is a cross-sectional survey conducted annually by Statistics Canada, a Canadian federal government organization, in partnership with Health Canada and the Public Health Agency of Canada. The survey was voluntary, and data collection was conducted according to the Statistics Act of Canada. It provides representative regional estimates of the health status, health determinants and healthcare utilization of people living in Canada every two years. Participants include those aged > 12 years living in any of Canada’s provinces or territories, with the following exclusions (representing <3% of the population): those in the provinces living on reserves or in other Aboriginal settlements, full-time members of the Canadian forces, those living in institutions, children aged 12-17 years in foster care, and certain regions of northern Quebec. We selected cycles 2015/16 and 2017/18 for analysis as these were the most recent cycles with a consistent sampling frame (changed after 2019) that were not impacted by changes in sampling methodology and response rate that occurred due to the COVID-19 pandemic. The response rate for cycle 2015/16 was 59.5% overall, while for 2017/18 it was 58.8%, with some geographic variation ( 19 , 20 ). Surveys were conducted by trained interviewers in-person or over the telephone (for the maternal experiences module 27% and 73%, respectively). Folic acid-containing supplement use Data on folic acid-containing supplement use was obtained from the Maternal Experiences module, which was administered as core content to respondents who reported being female and between 15-55 years of age at the time of the survey. Details of the specific questions and their administration are available in the Supplemental Materials . Respondents answered questions about their supplement use at the time of the survey (referred to henceforth as “current supplement use”), which we examined separately within participants who reported being currently pregnant, currently lactating but not pregnant (henceforth called “lactating”), and not currently pregnant. Respondents who reported having given birth in the last five years answered additional questions about their use of folic acid-containing supplements in the three months prior to their most recent pregnancy, and in the first three months of their most recent pregnancy. For ease of reporting, we refer to this period of supplementation as “peri-conceptional”. If they answered “Yes” to either question about folic acid-containing supplement use peri-conceptionally, they were asked a follow-up question regarding frequency. Respondents were also asked about their awareness of the link between folic acid and birth defects. Our final analytical sample included those who answered “yes” or “no” to these questions. Other variables We examined folic acid-containing supplement use by categories of respondents within sociodemographic, geographic, and health attributes available in CCHS identified a priori based on previous literature and knowledge of determinants of supplement use, folate status, or healthcare access. Details of the derivation and categorization of these variables is available in the Supplemental Materials. The variables included: age, highest level of education completed, household size-adjusted income, source of household income, marital status, immigration status, self-reported racial group or indigenous identity, province or territory of residence, region of residence, urban or rural location of residence, food security, BMI, daily consumption of fruits and vegetables, monthly consumption of green vegetables, smoking, alcohol use, and frequency of general physical checkup. Because folic acid-containing supplement use in the peri-conception period was assessed retrospectively, we additionally examined time since most recent birth (0 to 5 years) for these outcomes to assess the impact of recall bias. For all questions, missing data from responses “don’t know”, refusal or not stated were combined. Statistical Analysis All statistical analyses were carried out in SAS version 9.4 using the CCHS shared file with data from respondents who consented to data sharing with Health Canada and the Public Health Agency of Canada (93.6% for cycles 2015/16 and 93.1% for cycles 2017/18). Survey sampling weights from Statistics Canada were applied to all estimates of proportion to account for the sampling design and probability of selection so that study results can be considered representative of the population of Canada ( 19 , 20 ). We used the bootstrap method to calculate 95% confidence intervals of all estimates, applying 1000 bootstrap weights produced by Statistics Canada. Data from different cycles were combined with adjusted cycle weights per established Statistics Canada methodology ( 21 ). We fit regression models for the use of a folic-acid containing supplement or awareness of the link between folic acid and birth defects between categories of the sociodemographic, geographic and health variables in both a univariate model and in multivariable models adjusting for significant factors from the univariate analyses. Education was colinear with income, while region of residence overlapped in definition with province or territory of residence, so these sociodemographic factors were examined in separate models. The models for income variables, which were only recorded in 2017-18, were limited to respondents from this latter survey. Frequency of general physical checkup was included as optional content in the 2015/16 survey only and was answered by <50% of respondents, so this variable was examined in the univariate model only. The association between outcomes and factors was assessed using ANOVA, with p-value<0.05 to denote statistical significance. Post-hoc pairwise comparisons were conducted for factors with significant global associations, with odds ratios reported vs a pre-specified reference group. In line with Statistics Canada reporting requirements, we suppressed results for groups with a sample size 33.3% as unacceptable for reporting (replaced with the letter “F”), and flagged groups with a coefficient of variation (CV) of >16.6-33.2% to be interpreted with caution with the letter “E” ( 19 , 20 ). RESULTS A total of 59,345 females aged 15-55 years completed the Maternal Experiences module, including 29,635 from the 2015-16 cycle, and 29,710 from the 2017-18 cycle. The participant flow diagram is shown in Figure 1 . Current supplement use was stratified by pregnancy and lactation status: not pregnant or lactating, (n=53,559, mean age 36.1 [95% CI: 36.0, 36.2] years), lactating, (n=2069, mean age 32.3 [95% CI 32.0, 32.6], and pregnant (n=1,676, mean age 31.7 [95% CI: 31.2, 32.2] years). Among those who reported having given birth in the last five years, we assessed folic acid-containing supplement use in the three months prior to their most recent pregnancy (n=10,326, mean age at delivery 30.8 [95% CI: 30.6, 30.9] years), and during the first 3 months of their most recent pregnancy (n=10,329, mean age at delivery 30.8 [95% CI: 30.6, 30.9] years). We also examined awareness of the link between folic acid and some birth defects prior to pregnancy in this group (n=10,384, mean age at delivery 30.7 [95% CI: 30.6, 30.9] years). Download figure Open in new tab Figure 1 Participant Flow Prevalence of folic acid-containing supplement use Overall, 16.5% (95% CI: 15.9, 17.0) of females of childbearing age living in Canada who were not pregnant or lactating reported currently taking a vitamin supplement containing folic acid ( Table 1 ) . The proportion was highest in Alberta (21.7% [95% CI: 20.2, 23.2) and lowest in Nunavut 8.1% [95% CI: 3.5, 12.8] E) and Quebec (7.3% (95% CI: 6.5, 8.0). The proportion was higher among non-pregnant respondents who were lactating (58.4%, [95% CI 54.8, 61.9]) ( Table 2 ) and among those who reported being currently pregnant, (80.3% [95% CI: 77.1, 83.5]) ( Table 3 ). Among respondents who had given birth in the preceding 5 years, 76.3% (95% CI: 74.9, 77.6) reported that they had been aware prior to their pregnancy that taking folic acid can help prevent some birth defects ( Table 4 ) . Awareness was highest in Prince Edward Island (84.1%, [95% CI: 77.6, 90.7]) and lowest in Nunavut (18.1% [95% CI: 10.6, 25.5 E]. In the 3 months prior to becoming pregnant, 63.7% (95% CI: 62.2-65.1) of respondents reported that they had taken a folic acid-containing supplement ( Table 5 ) , with the highest proportions among respondents from Quebec (68.5% [95% CI: 65.7, 71.2]) and Prince Edward Island (68.1% [95% CI: 59.0, 77.3]), and the lowest proportion in Newfoundland and Labrador (49.1% [95% CI: 40.4, 57.8]) and Nunavut (22.4% [95% CI: 13.8, 30.9 E]). During the first 3 months of their most recent pregnancy, 89.9% reported having taken a folic acid-containing supplement (95% CI: 88.8, 90.9), with the highest proportions in Prince Edward Island (97.1% [95% CI: 94.3, 99.9]) and British Columbia (94.3% [95% CI: 92.4, 96.2]), and the lowest in Manitoba (84.0% [95% CI: 79.7, 88.2]) and Nunavut (54.9% [95% CI: 43.7, 66.1]) ( Table 6 ) . View this table: View inline View popup Table 1. Folic acid-containing supplement use by among females aged 15-55 who are neither pregnant or lactating 1 View this table: View inline View popup Table 2. Folic acid-containing supplement use by lactating females aged 15-55 1 View this table: View inline View popup Table 3. Folic acid-containing supplement use among pregnant females aged 15-55 1 . View this table: View inline View popup Table 4. Awareness of link between folic acid and some birth defects 1 . View this table: View inline View popup Table 5. Folic acid-containing supplement in the 3 months prior to becoming pregnant 1 . View this table: View inline View popup Table 6. Folic acid-containing supplement use in the first three months of pregnancy 1 . Factors associated with folic acid-containing supplement use For ease of interpretation, heat maps summarizing the odds ratios for the associations between folic acid-containing supplement use and the sociodemographic, geographic, and health factors examined are shown in Figures 2A (unadjusted) and 2B (adjusted for significant factors from univariate models, see Tables 1 - 6 and Supplemental Tables 1 -6 for details), with detailed results shown in the relevant tables. Data for some characteristics (source of household income, region of residence, type of community, BMI category, food security, consumption of green vegetables, consumption of total fruits and vegetables, frequency of general physical check-up, alcohol use, smoking, and years since birth of most recent infant [for those who reported giving birth in the past five years only]) are shown in the corresponding Supplemental Tables 1 -6 . In the interest of brevity and to decrease reliance on p-values, we focus our descriptions on patterns of associations that were consistent between similar outcomes and between the unadjusted and adjusted models. Unless otherwise stated, ORs provided in the text are for the adjusted model. Download figure Open in new tab Download figure Open in new tab Figure 2 Summary of regression results 1 Among respondents who had given birth in the preceding 5 years, awareness of the link between folic acid-containing supplements and some birth defects was the strongest predictor of supplement use. Those who were unaware of the link pre-pregnancy were less likely to report using folic acid-containing supplements in the 3 months prior to pregnancy (OR 0.20 [95% CI: 0.17, 0.24]) and in the first 3 months of pregnancy (OR 0.30 [95% CI: 0.24, 0.39]). Younger age was associated with a lower likelihood of using a folic acid-containing supplement currently among non-pregnant respondents (0.70 [95% CI: 0.63, 0.79]), and retrospectively among people who had given birth in the preceding 5 years pre-pregnancy (OR 0.80 [95% CI: 0.69, 0.93]), as well as with a lower odds of being aware of the link between folic acid and some birth defects (OR 0.48 [95% CI: 0.40, 0.57]). A similar trend was observed for folic acid-containing supplement use during pregnancy among those who had given birth in the last 5 years, though this did not remain significant upon adjustment. Educational attainment was associated with supplement use among non-pregnant and pregnant women, and awareness of the link between folic acid and some birth defects, with adjusted odds ratios ranging from 0.4 to 0.7 for high school compared to postsecondary, and 1.2 to 1.8 for bachelor’s degree or higher compared to postsecondary diploma. Marital status was associated with folic acid-containing supplement use at all outcomes, with respondents who reported not being married or in a common law relationship less likely to report taking a folic acid-containing supplement (ORs from 0.4 to 0.6) or to be aware of the link between folic acid and some birth defects (OR 0.42 [95% CI: 0.34, 0.52]). Having a household income > median was associated with a higher odds of taking a folic acid-containing supplement peri-conceptionally (OR 1.74 [95% CI: 1.38, 2.21] and 1.91 [95% CI: 1.35, 2.71] for the three months prior to and first 3 months of pregnancy respectively) and with a higher odds of being aware of the link between folic acid and some birth defects (OR 1.47 [95% CI: 1.11, 1.94]) among respondents who had given birth in the preceding 5 years. A similar trend was observed in the unadjusted model for current supplement use among pregnant, lactating, and non-pregnant respondents, but this did not reach statistical significance. Main source of household income from non-employment sources (social assistance, welfare, alimony or other) tended to associate with lower odds of supplement use during all life-stages, but this was significant in the adjusted model only for awareness of the link between folic acid and some birth defects (OR 0.53 [95% CI: 0.34, 0.82]). Moderate or severe food insecurity was consistently associated with lower odds of all outcomes, though this remained significant in the adjusted model only for awareness of the link between folic acid and some birth defects (ORs 0.61-0.66). Self-reported race or Indigenous identity demonstrated variable associations with folic acid-containing supplement use. For example, in the adjusted model, self-reported Black or South Asian race was associated with a higher odds of current folic acid-containing supplement use than those reporting a white race among non-pregnant respondents (OR 1.65 [95% CI: 1.28, 2.12]) and 1.66 [95% CI: 1.32, 2.08] respectively), but tended to associate with lower odds of folic acid-containing supplement use during pregnancy, though this was not always significant. There was a pattern of lower odds of folic-acid containing supplement use in the 3 months before and first 3 months of pregnancy among respondents who self-reported a non-white race or Indigenous identity relative to those reporting a white race, though upon adjustment, this remained significant only for the first 3 months of pregnancy among those who identified as Black or Inuit (OR 0.57 [95% CI: 0.33, 0.99] and 0.38 [95% CI: 0.17, 0.83] respectively), and only for the 3 months prior to their most recent pregnancy among those who identified as First Nations (OR 0.54 [95% CI: 0.39, 0.75]). All racial groups or Indigenous identities had a lower odds of reporting awareness of the link between folic acid and some birth defects relative to those reporting white race in the unadjusted mode, though in the adjusted model this remained significant only for respondents who identified as Black (OR 0.67 [95% CI: 0.46, 0.97]), Middle Eastern (OR 0.50 [95% CI: 0.30, 0.83]), South Asian (OR 0.58 [95% CI: 0.36, 0.93]) or First Nations (OR 0.44 [95% CI: 0.30, 0.65]). Among respondents who had given birth in the preceding 5 years, both recent and established immigrants to Canada had a lower odds of being aware of the link between folic acid and some birth defects (ORs 0.3-0.5), and were less likely to report having used a folic acid-containing supplement in the first 3 months of pregnancy (ORs 0.5-0.6) compared to those born in Canada. We identified no consistent pattern for associations with folic acid-containing supplement use by immigration among non-pregnant or lactating respondents, or those who reported being pregnant at the time of the survey. Associations by region or province of residence differed between outcomes, and few associations remained significant upon adjustment for other factors. Though this was not always statistically significant, Nunavut consistently had a lower odds of folic acid-containing supplement use relative to Ontario across life stages examined, and a substantially lower odds of reporting awareness of a link between folic acid and some birth defects (OR 0.08 (95% CI: 0.02, 0.27). BMI in the underweight or obese range was associated with a lower odds of folic acid-containing supplement use relative to those in the normal range in the 3 months prior to pregnancy among those who had given birth in the preceding 5 years (OR 0.71 for both), while BMI in the obese range was additionally associated with a lower odds of supplement use in the first three months of pregnancy (OR: 0.68 [95% CI: 0.46, <1.00]). BMI in the overweight range was not significantly associated with supplement use in any of the life stages examined. Likewise, BMI was not associated with awareness of the link between folic acid and birth defects in the adjusted model. Monthly intake of green vegetables or daily intake of fruits and vegetables was generally associated with lower odds of supplement use among non-pregnant and pregnant respondents, as well as during the periconceptional period in the unadjusted model, but this was attenuated upon adjustment. In contrast, for respondents who reported currently lactating, a lower intake of daily fruits and vegetables was associated with a higher odds of using a folic acid-containing supplement (OR 1.57 [1.01, 2.45]). Similarly, smoking consistently showed strong negative associations with folic acid supplement use or awareness of the link between folic acid and some birth defects in the unadjusted model (ORs 0.3-0.6), but was no longer significant upon adjustment for current supplement use among respondents who were lactating or pregnant. Alcohol use was negatively associated with folic acid-containing supplement use during current pregnancy and lactation (ORs 0.05-0.59) but was not associated with supplement use among non-pregnant women of childbearing age, or with awareness of the link with NTDs in the adjusted model. Frequency of general physical checkup was only available in a small subset of respondents for the 2015/16 survey, and was associated only with supplement use among non-pregnant women in the unadjusted model (OR 0.62 [95% CI: 0.44, 0.87]). Other studies have identified pregnancy intention as a determinant of folic acid-containing supplement use ( 22 ), but this variable was not available within our dataset. In an exploratory analysis, we examined folic acid-containing supplement use among non-pregnant females of childbearing age stratified by reported sexual behaviors as a proxy. Respondent who were not sexually active with males or who reported using a form of birth control were significantly less likely to report using a folic acid-containing supplement (OR 0.24, [95% CI: 0.20, 0.30] and 0.63 [0.56, 0.70] respectively, data not shown) than those who reported being sexually active with males and who did not use a form of birth control. DISCUSSION Our analysis provides recent, nationally representative estimates of folic acid-containing supplement use among females of reproductive age in Canada. These data are highly policy-relevant given Canadian recommendations that anyone who could become pregnant consume a daily multivitamin supplement containing folic acid, whether they are planning a pregnancy or not, continuing throughout pregnancy and lactation. Our paper provides data about supplement use pre-pregnancy, during the first trimester, and among females who are non-pregnant, pregnant, and, to our knowledge for the first time in national Canadian data, lactating. Previous nationally representative data from the Maternal Experiences Survey (MES) is now >15 years old and included only retrospective data on the 3 months before and first 3 months of pregnancy ( 23 ). A more recent analysis of the CCHS Maternal Experiences module investigated only awareness of the link between folic acid and some birth defects, and did not include disaggregation by race or Indigenous identity ( 24 ). Analyses of data from the CCHS Nutrition-2015 excluded pregnant and lactating women ( 25 ). Other Canadian research cohorts studies are not representative of the Canadian population, cannot provide provincial or territorial estimates, and are considerably smaller than the present analysis, which includes over 50 thousand respondents weighted to represent over 9 million women living in Canada. Our large, diverse sample also enabled us to look at associations between sociodemographic and health characteristics and supplement use, which are essential for assessing inequalities in Canada. These findings will also be informative for other countries, including the United States, which has similar initiatives. The proportion of respondents who reported using folic acid in the present analysis is higher than previously reported in the MES for 2006-7 for the 3 months prior to pregnancy (63.7% [95% CI: 62.2-65.1] vs 57.7% [95% CI: 56.4–59.0]), but is similar for the first 3 months of pregnancy (89.9% [95% CI: 88.8, 90.9] vs 89.7% [95% CI: 95% CI: 88.9–90.5]). The proportion of respondents who reported being aware prior to pregnancy that folic acid supplementation could help prevent some birth defects in our study (76.3% [95% CI: 74.9, 77.6]) was essentially unchanged compared to that reported in the 2006-7 MES (77.6% [95% CI: 76.6–78.7]), and was comparable to a recently published analysis using data from the 2017-18 CCHS (79%) ( 24 ). The prevalence of folic acid-containing supplement use during pregnancy in our nationally representative sample (80.3% [95% CI: 77.1, 83.5]) is within the range reported in other non-nationally representative Canadian cohorts; for example lower than reported in the Alberta Pregnancy Outcomes and Nutrition cohort (APrON, 91-97% ( 27 )), but higher than reported in Maternal-Infant Research on Environmental Chemicals cohort (MIREC, 78%, ( 26 )). In our analysis, estimates of folic acid-containing supplement use among non-pregnant females of childbearing age are lower than reported previously from the 2015 CCHS-Nutrition: 11.0% (95% CI: 10.2, 11.8) for those aged < 30, and 19.2% ( 95% CI: 18.5, 19.9) for those aged 31-55 in our study compared to 15.4% (SE 1.7) of those aged 14-18, 19.1% (SE 2.7) of those aged 19-30, and 24.7% (SE 1.7) of those aged 31-50 ( 25 ). This lower prevalence may be explained by differences in how folic acid containing supplement use was defined. The 2015 CCHS-Nutrition analysis classified respondents as supplement users if they reported using a supplement at least once in the previous 30 days in a food frequency questionnaire, whereas in our study, it was assessed by the question “are you taking a vitamin supplement containing folic acid?” which may not have captured sporadic or occasional supplement users. Canadian public health guidelines recommend that anyone who could become pregnant, is pregnant, or is lactating consume a daily multivitamin supplement containing 400 µg of folic acid ( 15 ). Taken together, our data suggest that adherence to Canadian guidelines to consume a supplement with folic acid is low among the general population of non-pregnant females of childbearing age. Despite this, a majority report using a supplement in line with the recommendation during pregnancy, and to a lesser extent before pregnancy and in lactation. In our analysis, respondents from Nunavut consistently reported lower prevalence of folic acid-containing supplement use across measures compared to respondents from other provinces or territories, as well as a substantially lower prevalence of awareness of the link between folic acid and some birth defects. While the associations were attenuated upon adjustment for other factors, such as age, marital status, income, and food insecurity, the pattern remained consistent. These results are similar to findings from the 2006-7 Maternity Experiences survey ( 23 ). Our results are also similar to the proportion of folic acid-containing supplement users among non-pregnant women of reproductive age in the 2007-8 Inuit Health Survey (8.1 vs 6.8%), the majority of whom were from Nunavut ( 23 , 31 ). The identification of this persistent inequality may be important for developing targeted public health initiatives. Our study also identified other sociodemographic and health factors associated with folic acid-containing supplement use or awareness of the link between folic acid and some birth defects. Notably, younger age, single marital status, lower educational attainment, income below the median, and smoking tended to associate with lower odds of using a supplement or of being aware of the link between folic acid and some birth defects. Similar associations were identified between general vitamin/mineral supplement use and respondent age, education, income, BMI, and smoking in the 2015 CCHS-Nutrition ( 25 ). These factors have also been associated with supplement use in other studies within Canada and the United States ( 22 , 32 ). The factors associated with lower odds of folic acid supplement use in our study reflect those associated with lower folate status. In an analysis of red blood cell folate status of female supplement non-users of childbearing age in the Canadian Health Measures Survey, those with younger age, lower educational attainment, lower income, or current smoking were more likely to have low folate status compared to other supplement non-users ( 33 ). Similar associations have been reported in U.S cohorts summarized by the Environmental influences on Child Health Outcomes (ECHO) consortium ( 34 ). This suggests that these subgroups of supplement non-users remain at higher risk for having an NTD-affected pregnancy despite mandatory folic acid fortification. Strengths of our study include its large, nationally representative sample, which enabled provincial and territorial-level estimates, the collection of detailed sociodemographic and health data, and the examination of folic acid-containing supplement use at multiple periods relevant both to the prevention of NTDs and to Canadian guidelines. Our study also has several limitations. The questions regarding folic acid-containing supplement use in the CCHS were broad “yes” or “no” questions, without information available on dose. In addition, while our analysis shows that the vast majority (>98%) of those who used folic acid-containing supplements peri-conceptionally reported taking them every day or almost every day, information on frequency of supplement use was unavailable for the question on current folic acid-containing supplement use. Further, questions referred to “folic acid”, a term in line with Canadian public health guidance specifying the use of this form of folate for NTD prevention ( 35 ) however, this may have caused an underestimation of supplement use among those unfamiliar with this term, or who used supplements containing another form of folate. There was also no information available in our survey on the trimester of current pregnancy, so it is possible that some of the pregnant respondents may have used supplements in the first trimester, but discontinued use thereafter. Another limitation of the retrospective nature of the questions about folic acid-containing supplement use peri-conceptionally is that many participant characteristics examined reflect the time at which the survey was conducted, which may have changed in the up to 5 years since respondents last gave birth. The associations with many of these characteristics, such as income, and education, were consistent between current and retrospective supplement use, which may give more confidence that these are important determinants despite this limitation. CONCLUSION While the majority of people living in Canada who are or have been pregnant report using folic acid-containing supplements peri-conceptionally, adherence to Canadian guidelines on folic acid supplementation among the general population of non-pregnant females of childbearing age is <20%, and inequalities remain by factors such as age, income, education, marital status, and geographic location. Awareness that folic acid supplements can prevent some birth defects is a strong predictor of supplement use, which makes it an important message for inclusion in public health education initiatives to improve adherence to guidelines. Sources of Support The Canadian Community Health Survey is conducted by Statistics Canada in partnership with Health Canada and the Public Health Agency of Canada. Authors Contributions All authors contributed to the design of the research, development of the analysis plan, study oversight, interpretation of results, and review and approval of the final manuscript. LL and TML performed the statistical analysis. KEH wrote the article with input from all coauthors. Data Availability Data described in the manuscript, code book, and analytic code will be made available upon request pending application and approval to Statistics Canada and Health Canada. Conflict of Interest HW is a JN Editorial Board Member. The other authors report no conflicts of interest. Editorial Board Membership Hope Weiler is an Editorial Board Member for The Journal of Nutrition and played no role in the Journal’s evaluation of the manuscript. Clinical trial registry number not applicable Registry and registry number for systematic reviews of meta-analysis not applicable Footnotes Author’s last names for indexing: Hopperton, Loukine, Luong, Nguyen, Bertinato, Bonvalot, Cooper, Luo, MacFarlane, McCrea, Nicholson, Rana, Vercammen, Yuan, Brule, Weiler Disclaimers: none. Abbreviations BMI Body Mass Index CCHS Canadian Community Health Survey CI Confidence Interval CV Coefficient of Variation NHANES National Health and Nutrition Examination Survey NTD Neural Tube Defects References 1. ↵ Czeizel AE , Dudás I . Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation . N Engl J Med 1992 ; 327 : 1832 – 5 . OpenUrl CrossRef PubMed Web of Science 2. ↵ MRC . Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research Group . Lancet 1991 ; 338 : 131 – 7 . OpenUrl CrossRef PubMed Web of Science 3. ↵ Crider KS , Qi YP , Yeung LF , Mai CT , Zauche LH , Wang A , Daniels K , Williams JL . Folic Acid and the Prevention of Birth Defects: 30 Years of Opportunity and Controversies . Annu Rev Nutr 2022 ; 42 : 423 – 52 . OpenUrl PubMed 4. ↵ Health Canada . Folic acid and neural tube defects . Internet: https://www.canada.ca/en/public-health/services/pregnancy/folic-acid.html ( accessed Jul 24 2024 ). 5. ↵ Black AY , Guilbert E , Hassan F , Chatziheofilou I , Lowin J , Jeddi M , Filonenko A , Trussell J . The cost of unintended pregnancies in Canada: estimating direct cost, role of imperfect adherence, and the potential impact of increased use of long-acting reversible contraceptives . J Obstet Gynaecol Can 2015 ; 37 : 1086 – 97 . OpenUrl PubMed 6. ↵ Finer LB . Unintended pregnancy among U.S. adolescents: accounting for sexual activity . J Adolesc Health 2010 ; 47 : 312 – 4 . OpenUrl CrossRef PubMed Web of Science 7. ↵ Government of Canada . Canada Gazette Part 2, Ottawa, Wednesday , November 25 , 1998 . Internet: https://publications.gc.ca/collections/collection_2013/gazette/SP2-2-132-24.pdf ( accessed Aug 26 2024 ). 8. ↵ De Wals P , Tairou F , Van Allen MI , Uh SH , Lowry RB , Sibbald B , Evans JA , Van den Hof MC , Zimmer P , Crowley M , et al. Reduction in neural-tube defects after folic acid fortification in Canada . N Engl J Med 2007 ; 357 : 135 – 42 . OpenUrl CrossRef PubMed Web of Science 9. ↵ Keats EC , Neufeld LM , Garrett GS , Mbuya MNN , Bhutta ZA . Improved micronutrient status and health outcomes in low- and middle-income countries following large-scale fortification: evidence from a systematic review and meta-analysis . Am J Clin Nutr 2019 ; 109 : 1696 – 708 . OpenUrl PubMed 10. ↵ Health Canada . About the data - Nutrition Surveillance Data Tool - Public Health Infobase | Public Health Agency of Canada . Internet: https://health-infobase.canada.ca/nutrition/usual-intakes/ ( accessed Jul 24 2024 ). 11. ↵ Health Canada . Reference Guide to Understanding and Using the Data - 2015 Canadian Community Health Survey—Nutrition . Internet: https://www.canada.ca/en/health-canada/services/food-nutrition/food-nutrition-surveillance/health-nutrition-surveys/canadian-community-health-survey-cchs/reference-guide-understanding-using-data-2015.html ( accessed November 2023 ). 12. ↵ Colapinto CK , O’Connor DL , Tremblay MS . Folate status of the population in the Canadian Health Measures Survey . CMAJ 2011 ; 183 : 13. ↵ Colapinto CK , Tremblay MS , Aufreiter S , Bushnik T , Pfeiffer CM , O’Connor DL . The direction of the difference between Canadian and American erythrocyte folate concentrations is dependent on the assay method employed: a comparison of the Canadian Health Measures Survey and National Health and Nutrition Examination Survey . Br J Nutr 2014 ; 112 : 1873 – 81 . OpenUrl PubMed 14. ↵ Tinker SC , Hamner HC , Qi YP , Crider KS. U . S. women of childbearing age who are at possible increased risk of a neural tube defect-affected pregnancy due to suboptimal red blood cell folate concentrations, National Health and Nutrition Examination Survey 2007 to 2012 . Birth Defects Res A Clin Mol Teratol 2015 ; 103 : 517 – 26 . OpenUrl CrossRef PubMed 15. ↵ Public Health Agency of Canada . Your Guide to a Healthy Pregnancy - Canada.ca . Internet: https://www.canada.ca/en/public-health/services/health-promotion/healthy-pregnancy/healthy-pregnancy-guide.html#a2 ( accessed Jul 24 2024 ). 16. ↵ Nelson CRM , Leon JA , Evans J . The relationship between awareness and supplementation: which Canadian women know about folic acid and how does that translate into use? Can J Public Health 2014 ; 105 : 40 . OpenUrl 17. Miller EC , Liu N , Wen SW , Walker M . Why do Canadian women fail to achieve optimal pre-conceptional folic acid supplementation? An observational study . J Obstet Gynaecol Can 2011 ; 33 : 1116 – 23 . OpenUrl PubMed 18. ↵ Government of Canada SC . Maternity Experiences Survey (MES) . Version current -10-24. Internet: https://www23.statcan.gc.ca/imdb/p2SV.pl?Function=getSurvey&SDDS=5019 ( accessed Aug 29 2024 ). 19. ↵ Statistics Canada . Canadian Community Health Survey (CCHS) Annual component User Guide 2017-18 . Internet: Available from: https://www.statcan.gc.ca/en/statistical-programs/document/5071_D4_V3 20. ↵ Statistics Canada . Canadian Community Health Survey (CCHS) Annual component User Guide 2015-16 . Internet: Available from: https://www.statcan.gc.ca/en/statistical-programs/document/5071_D4_V3 21. ↵ Statistics Canada . Instructions for Combining Multiple Cycles of Canadian Health Measures Survey (CHMS) Data . Internet: Available from: https://www.statcan.gc.ca/en/statistical-programs/document/5071_D4_V3 22. ↵ Tam LE , McDonald SD , Wen SW , Smith GN , Windrim RC , Walker MC . A survey of preconceptional folic acid use in a group of Canadian women . J Obstet Gynaecol Can 2005 ; 27 : 232 – 6 . OpenUrl PubMed 23. ↵ Public Health Agency of Canada . What Mothers Say: The Canadian Maternity Experiences Survey . Internet: https://www.canada.ca/content/dam/phac-aspc/migration/phac-aspc/rhs-ssg/pdf/survey-eng.pdf ( accessed July 2024 ). 24. ↵ Mehra VM , Greenblatt EM , Tamim H , Snelgrove JW , Jones CA . Prevalence and Associated Risk Factors with Unawareness of Folic Acid Benefits Prior to Pregnancy: Results From Canadian Community Health Survey . J Obstet Gynaecol Can 2024 ; 46 : 102670 . OpenUrl PubMed 25. ↵ Keshavarz P , Shafiee M , Islam N , Whiting SJ , Vatanparast H . Prevalence of vitamin-mineral supplement use and associated factors among Canadians: results from the 2015 Canadian Community Health Survey . Appl Physiol Nutr Metab 2021 ; 46 : 1370 – 7 . OpenUrl PubMed 26. ↵ Patti MA , Braun JM , Arbuckle TE , MacFarlane AJ . Associations between folic acid supplement use and folate status biomarkers in the first and third trimesters of pregnancy in the Maternal-Infant Research on Environmental Chemicals (MIREC) Pregnancy Cohort Study . Am J Clin Nutr 2022 ; 116 : 1852 – 63 . OpenUrl PubMed 27. ↵ Gómez MF , Field CJ , Olstad DL , Loehr S , Ramage S , McCargar LJ . Use of micronutrient supplements among pregnant women in Alberta: results from the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort . Matern Child Nutr 2013 ; 11 : 497 – 510 . OpenUrl PubMed 28. Vatanparast H , Adolphe JL , Whiting SJ . Socio-economic status and vitamin/ mineral supplement use in Canada . Health Rep 2010 ; 21 : 19 – 25 . OpenUrl PubMed 29. Gahche J , Bailey R , Burt V , Hughes J , Yetley E , Dwyer J , Picciano MF , McDowell M , Sempos C . Dietary supplement use among U.S. adults has increased since NHANES III (1988-1994) . NCHS Data Brief 2011 ; 1 – 8 . 30. Savikko N , Pitkälä KH , Laurila JV , Suominen MH , Tilvis RS , Kautiainen H , Strandberg TE . Secular trends in the use of vitamins, minerals and fish-oil products in two cohorts of community-dwelling older people in Helsinki--population-based surveys in 1999 and 2009 . J Nutr Health Aging 2014 ; 18 : 150 – 4 . OpenUrl PubMed 31. ↵ Duncan K , Erickson AC , Egeland GM , Weiler H , Arbour LT . Red blood cell folate levels in Canadian Inuit women of childbearing years: influence of food security, body mass index, smoking, education, and vitamin use . Can J Public Health 2018 ; 109 : 684 – 91 . OpenUrl PubMed 32. ↵ Goldberg BB , Alvarado S , Chavez C , Chen BH , Dick LM , Felix RJ , Kao KK , Chambers CD . Prevalence of periconceptional folic acid use and perceived barriers to the postgestation continuance of supplemental folic acid: survey results from a Teratogen Information Service . Birth Defects Res A Clin Mol Teratol 2006 ; 76 : 193 – 9 . OpenUrl CrossRef PubMed Web of Science 33. ↵ Shi Y , De Groh M , MacFarlane AJ . Socio-demographic and lifestyle factors associated with folate status among non-supplement-consuming Canadian women of childbearing age . Can J Public Health 2014 ; 105 : 166 . OpenUrl 34. ↵ Sauder KA , Harte RN , Ringham BM , Guenther PM , Bailey RL , Alshawabkeh A , Cordero JF , Dunlop AL , Ferranti EP , Elliott AJ , et al. Disparities in Risks of Inadequate and Excessive Intake of Micronutrients during Pregnancy . J Nutr 2021 ; 151 : 3555 – 69 . OpenUrl CrossRef PubMed 35. ↵ Public Health Agency of Canada . Your Guide to a Healthy Pregnancy . Version current -08-20. Internet: https://www.canada.ca/en/public-health/services/health-promotion/healthy-pregnancy/healthy-pregnancy-guide.html ( accessed Dec 2 2024 ). 36. World Health Organization . Periconceptional folic acid supplementation to prevent neural tube defects . Version current August. Internet: https://www.who.int/tools/elena/interventions/folate-periconceptional#:~:text=WHO%20Recommendations,400%20%CE%BCg%20folic%20acid%20daily). ( accessed August 2024 ). 37. Statistics Canada . Low income lines : what they are and how they are created.: CS75-0002/2016-2E-PDF - Government of Canada Publications - Canada.ca . Internet: https://publications.gc.ca/site/eng/9.819223/publication.html ( accessed Jul 11 2024 ). 38. Canadian Institute of Health information . Guidance on the Use of Standards for Race-Based and Indigenous Identity Data Collection and Health Reporting in Canada . Internet: https://www.cihi.ca/sites/default/files/document/guidance-and-standards-for-race-based-and-indigenous-identity-data-en.pdf ( accessed Oct 17 2023 ). View the discussion thread. Back to top Previous Next Posted January 24, 2025. Download PDF Supplementary Material Data/Code Email Thank you for your interest in spreading the word about medRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. Your Email * Your Name * Send To * Enter multiple addresses on separate lines or separate them with commas. You are going to email the following Folic acid-containing supplement use among females aged 15-55 in the Canadian Community Health Survey 2015-2018 Message Subject (Your Name) has forwarded a page to you from medRxiv Message Body (Your Name) thought you would like to see this page from the medRxiv website. Your Personal Message CAPTCHA This question is for testing whether or not you are a human visitor and to prevent automated spam submissions. Share Folic acid-containing supplement use among females aged 15-55 in the Canadian Community Health Survey 2015-2018 Kathryn E. Hopperton , Lidia Loukine , The Minh Luong , Loan Nguyen , Jesse Bertinato , Yvette Bonvalot , Marcia Cooper , Wei Luo , Amanda J. MacFarlane , Jennifer McCrea , Carley Nicholson , Huma Rana , Kelsey Vercammen , Jane Yuan , Shawn Brule , Hope A. Weiler medRxiv 2025.01.21.25320917; doi: https://doi.org/10.1101/2025.01.21.25320917 Share This Article: Copy Citation Tools Folic acid-containing supplement use among females aged 15-55 in the Canadian Community Health Survey 2015-2018 Kathryn E. Hopperton , Lidia Loukine , The Minh Luong , Loan Nguyen , Jesse Bertinato , Yvette Bonvalot , Marcia Cooper , Wei Luo , Amanda J. MacFarlane , Jennifer McCrea , Carley Nicholson , Huma Rana , Kelsey Vercammen , Jane Yuan , Shawn Brule , Hope A. Weiler medRxiv 2025.01.21.25320917; doi: https://doi.org/10.1101/2025.01.21.25320917 Citation Manager Formats BibTeX Bookends EasyBib EndNote (tagged) EndNote 8 (xml) Medlars Mendeley Papers RefWorks Tagged Ref Manager RIS Zotero Tweet Widget Facebook Like Google Plus One Subject Area Epidemiology Subject Areas All Articles Addiction Medicine (570) Allergy and Immunology (864) Anesthesia (302) Cardiovascular Medicine (4445) Dentistry and Oral Medicine (444) Dermatology (383) Emergency Medicine (609) Endocrinology (including Diabetes Mellitus and Metabolic Disease) (1515) Epidemiology (15236) Forensic Medicine (30) Gastroenterology (1127) Genetic and Genomic Medicine (6610) Geriatric Medicine (669) Health Economics (1000) Health Informatics (4549) Health Policy (1370) Health Systems and Quality Improvement (1613) Hematology (543) HIV/AIDS (1266) Infectious Diseases (except HIV/AIDS) (15926) Intensive Care and Critical Care Medicine (1104) Medical Education (623) Medical Ethics (147) Nephrology (668) Neurology (6613) Nursing (346) Nutrition (999) Obstetrics and Gynecology (1147) Occupational and Environmental Health (957) Oncology (3341) Ophthalmology (975) Orthopedics (369) Otolaryngology (420) Pain Medicine (436) Palliative Medicine (130) Pathology (665) Pediatrics (1694) Pharmacology and Therapeutics (693) Primary Care Research (714) Psychiatry and Clinical Psychology (5458) Public and Global Health (9244) Radiology and Imaging (2205) Rehabilitation Medicine and Physical Therapy (1370) Respiratory Medicine (1197) Rheumatology (596) Sexual and Reproductive Health (715) Sports Medicine (530) Surgery (713) Toxicology (99) Transplantation (289) Urology (265) (function(){function c(){var b=a.contentDocument||a.contentWindow.document;if(b){var d=b.createElement('script');d.innerHTML="window.__CF$cv$params={r:'a02444f75e27599e',t:'MTc3OTg3NzA0MQ=='};var a=document.createElement('script');a.src='/cdn-cgi/challenge-platform/scripts/jsd/main.js';document.getElementsByTagName('head')[0].appendChild(a);";b.getElementsByTagName('head')[0].appendChild(d)}}if(document.body){var a=document.createElement('iframe');a.height=1;a.width=1;a.style.position='absolute';a.style.top=0;a.style.left=0;a.style.border='none';a.style.visibility='hidden';document.body.appendChild(a);if('loading'!==document.readyState)c();else if(window.addEventListener)document.addEventListener('DOMContentLoaded',c);else{var e=document.onreadystatechange||function(){};document.onreadystatechange=function(b){e(b);'loading'!==document.readyState&&(document.onreadystatechange=e,c())}}}})();