Validity and reproducibility of a semi-quantitative food frequency questionnaire for use among Portuguese pregnant women

Maternal caffeine intake during pregnancy and the risk of childhood asthma by 10 years of age-Evidence from The Generation XXI birth cohort study

BACKGROUND

We aimed to investigate the association between maternal caffeine intake during pregnancy and asthma in children by 10 years of age.

METHODS

We considered 5585 mother-child pairs enrolled in a population-based birth cohort. Consumption of regular and decaffeinated coffee, black and green tea, and cola beverages before and during pregnancy was obtained through face-to-face interviews within 72 h after giving birth, and total caffeine intake (mg/day) was estimated. Medical diagnosis of asthma was assessed and spirometry with bronchodilation was performed at 10 years of age. We used adjusted regression models to estimate the association between the caffeine intake/day during pregnancy with asthma by 10 years of age, and a quadratic relationship was verified between them. Consumption of caffeine before pregnancy, gestational age, maternal years of schooling, maternal self-reported medical diagnosis of asthma, smoking status before and during pregnancy, and children's sex were considered as confounders. We used nonlinear least squares models to estimate the knot point and its respective confidence interval (CI).

RESULTS

A higher intake of caffeine/day decreased the odds of having childhood asthma at 10 years of age (adjusted odds ratio [OR] = 0.60, 95% CI: 0.41; 0.88). The estimated knot point was 92.7 mg of caffeine/day (95% CI: 36.3, 163.3), where the risk was 7.2%, while for no intake (0 mg) the risk was 8.8%.

CONCLUSION

Maternal caffeine intake up to an estimated intake of approximately 93 mg/day during pregnancy decreased childhood asthma risk by 10 years of age. Nonetheless, further studies are required to confirm our results.

KEY MESSAGE

Maternal caffeine intake during pregnancy up to an estimated intake of approximately 93 mg/day decreased the risk of asthma in children by 10 years of age, but considering caffeine's potential adverse effects on other health outcomes, further studies are needed to explore its link to childhood asthma.

Maternal macronutrient and energy intake during pregnancy: a systematic review and meta-analysis

BACKGROUND

Nutritional status during pregnancy can have a significant impact on infant and maternal health outcomes. To maintain maternal homeostasis and support fetal growth, adequate macronutrient and energy intake during pregnancy is essential. Therefore, this study sought to systematically review and meta-analyze macronutrient and energy intakes during pregnancy.

METHODS

A systematic review and meta-analysis was carried out based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The required data were collected from four databases including: Web of Sciences, ProQuest, Scopus, and PubMed, from 1 January 1980 to 30 May 2023, by using a combination of search terms (dietary pattern" OR "diet quality" OR "food habits" OR "nutrition surveys" OR "diet surveys" OR "food-frequency questionnaire" OR "diet record" OR "dietary recall") AND ( "pregnancy" OR "reproduction" OR "maternal health" OR "neonatal outcomes") among interventional and observational studies. Excel and STATA version 11 were used for data analysis.

RESULTS

Among 7081 published articles, 54 studies were included in the review. Most of the 33 (61%) studies were cohort studies and a total of 135,566 pregnant women were included. The overall average of energy, carbohydrate, fat, and protein intake was 2036.10 kcal/day, 262.17 gr/day, 74.17 gr/day, and 78.21 gr/day, respectively. Also, energy intake during pregnancy was higher in American (2228.31 kcal/day, CI95%: 2135.06-2325.63) and Eastern Mediterranean regions (2226.70 kcal/day, CI95%: 2077.23-2386.92) than other regions (P < 0.001). Energy intake was higher in the third trimester than others (2115.64 kcal/day, CI95%: 1974.15-2267.27). Furthermore, based on the findings, there was a significant difference between energy intake in different World Health Organization (WHO) regions (P < 0.05).

CONCLUSIONS

According to the results of meta-analysis, the average total energy was below than average total energy required during pregnancy. More efforts are needed to encourage women to adopt healthy eating habits during pregnancy to support healthy fetal and infant development.

Eating Habits During Pregnancy of Women Giving Birth Very Prematurely: An Exploratory Analysis

INTRODUCTION

Preterm birth is increasing worldwide, representing a major cause of death and long-term loss of human potential among survivors. Some morbidities during pregnancy are well-known risk factors for preterm labor, but it is not yet known whether deviations from adequate dietary patterns are associated with preterm delivery. Diet may be an important modulator of chronic inflammation, and pro-inflammatory diets during pregnancy were reported to be associated with preterm birth. The aim of this study was to assess the food consumption during pregnancy of Portuguese women giving birth very prematurely and the association between the food consumption and the major maternal morbidities during pregnancy related with preterm delivery.

MATERIAL AND METHODS

A single-center cross-sectional observational study including consecutive Portuguese women giving birth before 33 weeks of gestation was conducted. Recall of eating habits during pregnancy was obtained within the first week after delivery, using a semi quantitative food frequency questionnaire validated for Portuguese pregnant women.

RESULTS

Sixty women with a median age of 36.0 years were included. Of these, 35% were obese or overweight at the beginning of pregnancy, 41.7% and 25.0% gained excessive or insufficient weight during pregnancy, respectively. Pregnancy-induced hypertension was present in 21.7% of cases, gestational diabetes in 18.3%, chronic hypertension in 6.7%, and type 2 diabetes mellitus in 5.0%. Pregnancy-induced hypertension was significantly associated with increased daily consumption of pastry products (31.2 vs 10.0 g, p = 0.022), fast food (39.6 vs 29.7 g, p = 0.028), bread (90.0 vs 50.0 g, p = 0.005), pasta, rice and potatoes (225.7 vs 154.3 g, p = 0.012). In a multivariate analysis, only bread consumption maintained a significant, albeit weak, association (OR = 1.021; 1.003 - 1.038, p = 0.022).

CONCLUSION

Pregnancy-induced hypertension was associated with increased consumption of pastry products, fast food, bread, pasta, rice, and potatoes, although only bread consumption had a weak but statistically significant association with pregnancy-induced hypertension in a multivariate analysis.

Reliability and Concurrent and Construct Validity of a Food Frequency Questionnaire for Pregnant Women at High Risk to Develop Fetal Growth Restriction

Accuracy of dietary assessment instruments such as food frequency questionnaire (FFQ) is crucial in the evaluation of diet–disease relationships. Test–retest reliability and concurrent and construct validity of a FFQ were evaluated in 150 pregnant women at high risk to develop fetal growth restriction randomly selected from those included in the improving mothers for better prenatal care trial Barcelona (IMPACT BCN). The FFQ and dietary records were performed at baseline and 34–36 weeks of gestation. Test–retest reliability of the FFQ for 12 food groups and 17 nutrients was moderate (ICC = 0.55) and good (ICC = 0.60), respectively. Concurrent validity between food, nutrients and a composite Mediterranean diet score (MedDiet score) and food records was fair for foods and nutrients (ρ average = 0.38 and 0.32, respectively) and moderate (r = 0.46) for the MedDiet score. Validation with biological markers ranged from poor (r = 0.07) for olives to moderate (r = 0.41) for nuts. A fair concordance between methods were found for nutrients (weighted κ = 0.22) and foods (weighted κ = 0.27). The FFQ-derived MedDiet score correlated in anticipated directions with intakes of nutrients and foods derived by food records. The FFQ showed a moderate test–retest reliability and reasonable validity to rank women according to their food and nutrient consumption and adherence to the Mediterranean diet.

Diet during pregnancy: Influence of social characteristics and migration in the ELFE cohort

Better adherence to dietary guidelines during pregnancy is supposed to result in healthier perinatal outcomes. We aim to characterize the diets of pregnant women by hypothesis‐driven and exploratory approaches and describe potential social determinants. Analyses included 12 048 mothers from the French nationwide ELFE birth cohort. Dietary intake over the last three months of the pregnancy was assessed by a food frequency questionnaire. Two hypothesis‐driven scores (the Diet Quality score, based on benchmarks derived from the National Health and Nutrition Program Guidelines, and the PANDiet score, based on nutrient intake) were calculated. Exploratory dietary patterns were also identified by principal component analysis. Multiple linear regressions were used to assess associations of maternal social characteristics with dietary patterns, accounting for the possible effect modification by their migration status. Five dietary patterns were identified: the Western, Balanced, Bread and toppings, Processed products, and Milk and breakfast cereals. Younger maternal age, single motherhood, unemployment and the presence of older children in the household were related to a suboptimal diet during pregnancy. The less acculturated the women were, the healthier and less processed their diets were, independent of their socio‐economic position. Several social determinants of the quality of women's diets were however moderated by their migration status. These findings shed light on the relations between indicators of social vulnerability, such as single motherhood and unemployment, and poorer diet quality. Given the reduced diet quality that accompanies the acculturation process, it is of paramount importance to identify the specific factors or obstacles that affect migrant women in maintaining their diet quality advantage over the majority population.

Impact of iodine supplementation during preconception, pregnancy and lactation on maternal thyroid homeostasis and offspring psychomotor development: protocol of the IodineMinho prospective study

BACKGROUND

Iodine deficiency is the most common cause of preventable brain harm and cognitive impairment in children. Portuguese women of childbearing age, pregnant women and their progeny were shown to have inadequate iodine intake. Consequently, the Portuguese Health Authorities have recommended a daily supplementation with 150-200 µg iodine in preconception, pregnancy, and lactation. The IodineMinho study intends to evaluate whether (i) this recommendation impacted on the prevalence of iodine deficiency in pregnant women from the Minho region of Portugal, (ii) the time of initiation of iodine supplementation (if any) influences the serum levels of thyroid hormones at several intervals during pregnancy and (iii) there are serum thyroid-hormone parameters in the 1st trimester of pregnancy that predict psychomotor development of the child at 18 months of age.

METHODS

Most Portuguese women are followed throughout pregnancy in community Family Health Units, where family physicians may choose to follow the National recommendation or other, concerning iodine sufficiency. This study will recruit women (N = 304) who intend to become pregnant or are already pregnant from 10 representative Units. Physician's approach and prescriptions, sociodemographic, nutrition and clinical information will be obtained at baseline and throughout pregnancy. To evaluate endocrine function, blood and urine samples will be collected at recruitment, once in each trimester of pregnancy, at delivery and 3 months after delivery. Breastmilk samples will be collected for iodine and energy content analysis. Children will be evaluated for psychomotor development at 18 months. Maternal thyroid volume will be evaluated by ultrasound scan at baseline, in the 3rd trimester and at 3 months after delivery.

DISCUSSION

Iodine deficiency early during development precludes children from achieving full intellectual capabilities. This protocol describes a study that is innovative and unique in its detailed and comprehensive evaluation of maternal and child endocrine and psychomotor parameters. By evaluating the effectiveness of the iodine supplementation recommendation, it will contribute to the public health systems' efforts to provide excellence in maternal and infant care.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04288531 . Registered 28 February 2020-Retrospectively registered.

Dietary Iron Intake in Pregnant Women in Europe: A Review of 24 Studies from 14 Countries in the Period 1991-2014

OBJECTIVE

Assessment of dietary iron intake in pregnant women in Europe.

DESIGN

Review. Setting. Literature search of dietary surveys reporting the intake of dietary iron using the PubMed and Google Scholar databases covering the years 1990-2019.

SUBJECTS

Healthy pregnant women.

RESULTS

24 dietary surveys/studies in 14 European countries were included. Nine studies (38%) used Food Frequency Questionnaires, which yielded significantly higher iron intake than studies using Dietary Records. Results from Dietary Record studies in 11 countries showed that iron intake varied between 8.3-15.4 mg/day with an estimated "median" value of 10-11 mg/day. Spain, Bosnia, and Poland reported an intake of 8.3-10.1 mg/day, Croatia, England, Norway, and Finland an intake of 10.2-11.4 mg/day, and Germany, Portugal, Czech Republic, and Greece an intake of 12.2-15.4 mg/day. The recommended iron intake in the various countries varied from 14.8-30 mg/day. In all studies, 60-100% of the women had a dietary iron intake below the recommended intake.

CONCLUSIONS

In Europe, the majority of pregnant women have a dietary iron intake, which is markedly below the recommended intake. This contributes to a low iron status in many pregnant women. Most guidelines do not advice routine iron supplements, while two guidelines (World Health Organization and Nordic Nutrition Recommendations) recommend routine iron supplementation during pregnancy. Within the European community, we need to reach consensus on the various guidelines and on the issue of iron supplementation. We should establish common European standardized dietary methods, uniform Dietary Reference Values, and uniform statistical methods in order to perform more reliable comparisons between studies in different countries.

Food and Nutrient Intake during Pregnancy in Relation to Maternal Characteristics: Results from the NICE Birth Cohort in Northern Sweden

Linkages between diet and other lifestyle factors may confound observational studies. We used cluster analysis to analyze how the intake of food and nutrients during pregnancy co-varies with lifestyle, clinical and demographic factors in 567 women who participated in the NICE (nutritional impact on immunological maturation during childhood in relation to the environment) birth-cohort in northern Sweden. A food frequency questionnaire, Meal-Q, was administered in pregnancy Week 34, and the reported food and nutrient intakes were related to maternal characteristics such as age, education, rural/town residence, parity, pre-pregnancy smoking, first-trimester BMI, allergy and hyperemesis. Two lifestyle-diet clusters were identified: (1) High level of education and higher age were related to one another, and associated with a diet rich in fruits, vegetables, whole grains and fish, and (2) smoking before pregnancy and higher BMI in early pregnancy were related to one another and associated with a diet that contained white bread, French fries, pizza, meat, soft drinks, candy and snacks. More than half of the women had lower-than-recommended daily intake levels of vitamin D, folate, selenium, and iodine. Complex lifestyle-diet interactions should be considered in observational studies that link diet and pregnancy outcome.

The Impact of Maternal Eating Disorders on Dietary Intake and Eating Patterns during Pregnancy: A Systematic Review

Maternal nutrition in pregnancy has a key influence on optimum fetal health. Eating disorders (EDs) during pregnancy may have detrimental effects on fetal growth and the child’s early development. There is limited knowledge concerning the eating behavior, dietary intake and derived nutritional biomarkers as well as the nutrient supplementation in women with EDs during pregnancy. We performed a systematic review according to the PRISMA statement to synthesize current evidence in this field. Of N = 1203 hits, 13 full-texts were included in the qualitative synthesis. While women with current Binge Eating Disorder (BED) showed higher energy and fat intakes during pregnancy, women with a lifetime Anorexia Nervosa (AN), Bulimia Nervosa (BN) or both (AN + BN) had similar patterns of nutrient intake and dietary supplement use as healthy women. There is evidence, that women with a history of EDs have a sufficient diet quality and are more likely to be vegetarian. Dieting and bingeing improved substantially with pregnancy. The highlighted differences in the consumption of coffee/caffeine and artificially sweetened beverages as well as the elevated prevalence of iron deficiency anemia in women with a past or active ED during pregnancy might have an important impact on fetal development.

Validity and Reproducibility of a Food Frequency Questionnaire for Estimating Macro- and Micronutrient Intakes Among Pregnant Women in Jordan

Objectives: Assessing the relationship between maternal diet and pregnancy outcomes is a crucial issue that requires valid dietary assessment tools in this critical period. This study aimed to develop and assess the validity and reproducibility of a culture-specific quantitative food frequency questionnaire (QFFQ) to evaluate the dietary intake of macro- and micronutrients from food in a sample of Jordanian pregnant women.Methods: A QFFQ was validated against three repeated 24-hour dietary recalls (24-hr recalls). The QFFQ was administered twice one month apart. A total of 131 Jordanian pregnant women participated in the validation study. Thirty women took part in the reproducibility phase, which was repeated in a time frame of one month.Results: The intra-class correlation coefficients of QFFQ1 and QFFQ2 for energy were 0.79 and for macronutrients ranged from -0.27 for insoluble fiber to 0.81 for dietary fiber, indicating adequate (0.51) reproducibility. The intra-class correlation coefficients between two QFFQs for micronutrients ranged from 0.19 for selenium to 0.85 for vitamin C. The average of correlation coefficient was 0.58 for micronutrients. Energy-adjusted and de-attenuated Pearson correlation coefficients between QFFQ1 and 24-hr dietary recall for macronutrients ranged from 0.13 for soluble fiber and trans fat to 0.90 for cholesterol and for micronutrients from 0.01 for sodium to 0.78 for magnesium.Conclusions: The newly developed QFFQ could facilitate the assessment of the nutrient intake among Jordanian pregnant women. Using this QFFQ will help in evaluating the nutritional status of pregnant women, aiming at improving maternal and newborn health.

Impact of a healthy lifestyle intervention program during pregnancy on women and newborn: STUDY PROTOCOL for a quasi-experimental study

Physical activity during pregnancy assumes an important role in the health of both the pregnant and newborn. Given that physical activity tends to decrease throughout this period, it is essential to inform and encourage pregnant women to acquire healthy lifestyles, enabling them to improve their physical and psychological well-being.

This study aims to evaluate the impact of an intervention program on pregnant, newborn, and gestation outcomes, by increasing physical activity levels during this important period of woman's life.

This study will be conducted with 410 pregnant women in the first trimester. Participants will be recruited through the central hospital or community centers. Following consent and baseline data collection, pregnant women who do not have any medical or obstetric contraindication for physical exercise, will be assigned to the control or intervention groups. There will be 3 assessment periods: baseline (time 1—between the 7th and 10th week of gestation), after the intervention (time 2—between the 1st and 3rd day after delivery), and follow-up (time 3—1 month after delivery). The intervention group will have an intervention program, which comprises 2 terms: (1) teachers’ training delivered by researchers and (2) intervention delivered to pregnant women by trained teachers, which consists in 3 weekly classes of physical exercise (45/50 min each). The control group will have the standard care that is usually provided by health professionals.

The research has been approved by the Subcommittee on Ethics for the Life Sciences and Health of the University of Minho (id: SECVS 086/2015) and by the Ethics Committee for Health from the Central Hospital (id: 056/2014). There is a registration in clinical trials.gov, with the reference NCT03045237 (02/2017).

This study has the potential to increase pregnant's physical activity levels and contribute to programs and policies developed to optimize lifestyles during pregnancy and with implications in newborn outcomes.

Pre-pregnancy BMI, gestational weight gain and body image are associated with dietary under-reporting in pregnant Japanese women

Dietary under-reporting is a common problem when using self-reported dietary assessment tools. However, there are few studies regarding under-reporting during pregnancy. This study aimed to explore the demographic and psychosocial characteristics related to dietary under-reporting in pregnant Japanese women. A cross-sectional study was conducted between 2010 and 2011 at a university hospital in Tokyo, Japan. Nutrient intake was assessed using a self-administered Diet History Questionnaire (DHQ), which had questions about the consumption frequency and portion size of selected food items. The 24-h urinary excretion levels of urea N and K were used as the dietary protein and K intake reference values, respectively. Under-reporting of protein and K was defined as the bottom 25 % of the reporting accuracy (the ratio of reported intake on the DHQ to the estimated intake based on urinary excretion). Under-reporters were defined as participants who under-reported both protein and K intake. Multiple logistic regression analysis was performed to examine the factors associated with under-reporters. Of 271 healthy women at 19-23 weeks of gestation, thirty-five participants (12·9 %) were identified as under-reporters. Under-reporters had a lower pre-pregnancy BMI (adjusted OR (AOR) = 0·81) and lower gestational weight gain (AOR = 0·82); they also reported managing their gestational weight gain with the aim to return to their pre-pregnancy weight soon after childbirth (AOR = 2·99). Healthcare professionals should consider the potential for dietary under-reporting and the possible related factors when assessing the dietary intakes of pregnant Japanese women using self-administered questionnaires.

Association of maternal characteristics and behaviours with 4-year-old children's dietary patterns

This study examined the association of family and maternal characteristics with preschool children's dietary patterns. Trained interviewers evaluated subsample 3422 mothers and children enrolled in the population-based birth cohort Generation XXI (Porto, Portugal, 2005-2006). Maternal characteristics and behaviours (exercise, smoking habits, diet and child-feeding practices) and family characteristics were evaluated. Maternal diet was classified by a dietary score, and children's dietary patterns were identified by latent class analysis. Odds ratios (OR) and confidence intervals (95% CI) were estimated by multinomial regression models. The analysis was based on a framework with four conceptual levels: maternal socio-economic position (SEP) at 12 years, maternal socio-economic and demographic characteristics at child's delivery, family characteristics and maternal behaviours at child's 4 years. Three dietary patterns were identified in children: high in energy-dense foods (EDF); low in foods typically consumed at main meals and intermediate in snacks (Snacking); higher in healthy foods; and lower in unhealthy ones (Healthier, reference). Lower maternal SEP had an overall effect on children's diet (low vs. high SEP; EDF, OR = 1.76, 95% CI: 1.42-2.18; Snacking, OR = 1.73, 95% CI: 1.27-2.35), while maternal education was directly associated with it (≤9 vs. >12 schooling years, EDF, OR = 2.19, 95% CI: 1.70-2.81; Snacking, OR = 2.22, 95% CI: 1.82-3.55). Children whose mothers had worse dietary score were significantly more likely to follow unhealthier patterns (first vs. fourth quartile; EDF, OR = 9.94, 95% CI: 7.35-13.44, P-trend < 0.001; Snacking, OR = 4.21, 95% CI: 2.94-6.05, P-trend < 0.001). Maternal diet was the key factor associated with children's diet, above and beyond socio-economic and demographic characteristics, accounting for one-third of the determination coefficient of the fully adjusted model. At preschool age, interventions should give a particular focus on maternal diet and low SEP groups.

Development and validation of a food frequency questionnaire for dietary intake assessment among multi-ethnic primary school-aged children

INTRODUCTION

This study aimed to develop and validate a food frequency questionnaire (FFQ) to assess habitual diets of multi-ethnic Malaysian children aged 7-12 years.

METHODS

A total of 236 primary school children participated in the development of the FFQ and 209 subjects participated in the validation study, with a subsample of 30 subjects participating in the reproducibility study. The FFQ, consisting of 94 food items from 12 food groups, was compared with a three-day dietary record (3DR) as the reference method. The reproducibility of the FFQ was assessed through repeat administration (FFQ2), seven days after the first administration (FFQ1).

RESULTS

The results of the validation study demonstrated good acceptance of the FFQ. Mean intake of macronutrients in FFQ1 and 3DR correlated well, although the FFQ intake data tended to be higher. Cross-classification of nutrient intake between the two methods showed that < 7% of subjects were grossly misclassified. Moderate correlations noted between the two methods ranged from r = 0.310 (p < 0.001) for fat to r = 0.497 (p < 0.001) for energy. The reproducibility of the FFQ, as assessed by Cronbach's alpha, ranged from 0.61 (protein) to 0.70 (energy, carbohydrates and fat). Spearman's correlations between FFQ1 and FFQ2 ranged from rho = 0.333 (p = 0.072) for protein to rho = 0.479 (p < 0.01) for fat.

CONCLUSION

These findings indicate that the FFQ is valid and reliable for measuring the average intake of energy and macronutrients in a population of multi-ethnic children aged 7-12 years in Malaysia.

Nutritional supplements use in high-performance athletes is related with lower nutritional inadequacy from food

BACKGROUND

The use of nutritional supplements (NS) among athletes is widespread. However, little is known about the relationship between nutritional adequacy and NS usage. The aims of this study were to evaluate the NS usage and to compare the nutritional intake from food and prevalence of micronutrient inadequacy (PMI) between NS users and non-users.

METHODS

Portuguese athletes from 13 sports completed an NS usage questionnaire and a semi-quantitative food-frequency questionnaire assessing information over the previous 12 months. The estimated average requirement cut-point method was used to calculate PMI. General linear models were used to compare nutritional intake and NS usage. Chi-squared tests and logistic regression were performed to study, respectively, relationships and associations between PMI and NS usage.

RESULTS

From the 244 athletes (66% males, 13-37 years), 64% reported NS usage. After adjustment, NS users showed a higher intake from food (p < 0.05), for at least 1 gender, for energy, and for 7 of the 17 studied nutrients. The highest PMI were seen for vitamins D and E, calcium, folate, and magnesium. After adjustment, NS users, irrespective of gender, reported lower PMI for calcium (OR = 0.28, 95%CI: 0.12-0.65), and female users for magnesium (OR = 0.06, 95%CI: 0.00-0.98).

CONCLUSION

Athletes using NS reported a higher nutritional intake from food, and a lower PMI for several nutrients. Perhaps, those who were taking NS were probably the ones who would least benefit from it.

Development and Validation of a Mediterranean Oriented Culture-Specific Semi-Quantitative Food Frequency Questionnaire

The objectives were to develop a Mediterranean oriented semi-quantitative food frequency questionnaire (FFQ) and evaluate its validity in measuring energy and nutrient intakes. For FFQ development, the main challenge was to merge food items and practices reflecting cultural Mediterranean preferences with other food choices ensuing from diet transition to more westernized dietary patterns. FFQ validity was evaluated by comparing nutrient intakes against the average of two 24-h dietary recalls for 179 pregnant women. Although the mean intake values for most nutrients and energy tended to be higher when determined by the FFQ, the Cohen's d was below 0.3. Bland-Altman plots confirmed the agreement between the two methods. Positive significant correlations ranged from 0.35 to 0.77. The proportion of women classified correctly was between 73.2% and 92.2%, whereas gross misclassification was low. Weighted kappa values were between 0.31 and 0.78, while intraclass correlation coefficients were between 0.49 and 0.89. Our methodological approach for the development and validation of this FFQ provides reliable measurements of energy, macro- and micronutrient intakes. Overall, our culture-specific FFQ could serve as a useful assessment tool in studies aiming at monitoring dietary intakes, especially in the Mediterranean region, where countries share common cultural dietary habits.

Relative validity of a semi-quantitative, web-based FFQ used in the 'Snart Forældre' cohort - a Danish study of diet and fertility

OBJECTIVE

To assess the relative validity of a semi-quantitative, web-based FFQ completed by female pregnancy planners in the Danish 'Snart Forældre' study.

DESIGN

We validated a web-based FFQ based on the FFQ used in the Danish National Birth Cohort against a 4 d food diary (FD) and assessed the relative validity of intakes of foods and nutrients. We compared means and medians of intakes, and calculated Pearson correlation coefficients and de-attenuated coefficients to assess agreement between the two methods. We also calculated the proportion correctly classified based on the same or adjacent quintile of intake and the proportion of grossly misclassified (extreme quintiles).

SETTING

Participants (n 128) in the 'Snart Forældre' study who had completed the web-based FFQ were invited to participate in the validation study.

SUBJECTS

Participants in the 'Snart Forældre' study, in total ninety-seven women aged 20-42 years.

RESULTS

Reported intakes of dairy products, vegetables and potatoes were higher in the FFQ compared with the FD, whereas reported intakes of fruit, meat, sugar and beverages were lower in the FFQ than in the FD. Overall the de-attenuated correlation coefficients were acceptable, ranging from 0·33 for energy to 0·93 for vitamin D. The majority of the women were classified in the same or adjacent quintile and few women were misclassified (extreme quintiles).

CONCLUSION

The web-based FFQ performs well for ranking women of reproductive age according to high or low intake of foods and nutrients and, thus, provides a solid basis for investigating associations between diet and fertility.

Reproducibility and relative validity of a semi-quantitative food frequency questionnaire for Chinese pregnant women

BACKGROUND

Food frequency questionnaire (FFQ) is a reliable tool to estimate dietary intake in large nutritional epidemiological studies, but there is lack of a current and validated FFQ for use in urban Chinese pregnant women. This study aimed to evaluate the reproducibility and validity of a semi-quantitative FFQ designed to estimate dietary intake among urban pregnant women in a cohort study conducted in central China.

METHODS

In the reproducibility study, a sample of 123 healthy pregnant women completed the first FFQ at 12-13 weeks gestation and the second FFQ 3-4 weeks later. To validate the FFQ, the pregnant women completed three 24-h recalls (24HRs) between the intervals of two FFQs.

RESULTS

The intraclass correlation coefficients of two administrations of FFQ for foods ranged from 0.23 (nuts) to 0.49 (fruits) and for nutrients from 0.24 (iodine) to 0.58 (selenium) and coefficients were all statistically significant. The unadjusted Pearson correlation coefficients between two methods ranged from 0.28 (beans) to 0.53 (fruits) for foods and from 0.15 (iodine) to 0.59 (protein) for nutrients. Energy-adjusted and de-attenuated correlation coefficients for foods ranged from 0.35 (beans) to 0.56 (fruits) and for nutrients from 0.11 (iodine) to 0.63 (protein), and all correlations being statistically significant except for iodine, sodium and riboflavin. On average, 67.0% (51.2%-80.5%) of women were classified by both methods into the same or adjacent quintiles based on their food intakes, while 68.5% (56.1%-77.2%) of women were classified as such based on nutrient intakes. Extreme misclassifications were very low for both foods (average of 2.0%) and nutrients (average of 2.2%). Bland-Altman Plots also showed reasonably acceptable agreement between two methods.

CONCLUSION

This FFQ is a reasonably reliable and valid tool for assessing most food and nutrient intakes of urban pregnant women in central China.

The effect of long-chain polyunsaturated fatty acids intake during pregnancy on adiposity of healthy full-term offspring at birth

OBJECTIVE

The adjusted effect of long-chain polyunsaturated fatty acid (LCPUFA) intake during pregnancy on adiposity at birth of healthy full-term appropriate-for-gestational age neonates was evaluated.

STUDY DESIGN

In a cross-sectional convenience sample of 100 mother and infant dyads, LCPUFA intake during pregnancy was assessed by food frequency questionnaire with nutrient intake calculated using Food Processor Plus. Linear regression models for neonatal body composition measurements, assessed by air displacement plethysmography and anthropometry, were adjusted for maternal LCPUFA intakes, energy and macronutrient intakes, prepregnancy body mass index and gestational weight gain.

RESULT

Positive associations between maternal docosahexaenoic acid intake and ponderal index in male offspring (β=0.165; 95% confidence interval (CI): 0.031-0.299; P=0.017), and between n-6:n-3 LCPUFA ratio intake and fat mass (β=0.021; 95% CI: 0.002-0.041; P=0.034) and percentage of fat mass (β=0.636; 95% CI: 0.125-1.147; P=0.016) in female offspring were found.

CONCLUSION

Using a reliable validated method to assess body composition, adjusted positive associations between maternal docosahexaenoic acid intake and birth size in male offspring and between n-6:n-3 LCPUFA ratio intake and adiposity in female offspring were found, suggesting that maternal LCPUFA intake strongly influences fetal body composition.

Relative validity of micronutrient and fiber intake assessed with two new interactive meal- and Web-based food frequency questionnaires

BACKGROUND

The meal- and Web-based food frequency questionnaires, Meal-Q and MiniMeal-Q, were developed for cost-efficient assessment of dietary intake in epidemiological studies.

OBJECTIVE

The objective of this study was to evaluate the relative validity of micronutrient and fiber intake assessed with Meal-Q and MiniMeal-Q. The reproducibility of Meal-Q was also evaluated.

METHODS

A total of 163 volunteer men and women aged between 20 and 63 years were recruited from Stockholm County, Sweden. Assessment of micronutrient and fiber intake with the 174-item Meal-Q was compared to a Web-based 7-day weighed food record (WFR). Two administered Meal-Q questionnaires were compared for reproducibility. The 126-item MiniMeal-Q, developed after the validation study, was evaluated in a simulated validation by using truncated Meal-Q data.

RESULTS

The study population consisted of approximately 80% women (129/163) with a mean age of 33 years (SD 12) who were highly educated (130/163, 80% with >12 years of education) on average. Cross-classification of quartiles with the WFR placed 69% to 90% in the same/adjacent quartile for Meal-Q and 67% to 89% for MiniMeal-Q. Bland-Altman plots with the WFR and the questionnaires showed large variances and a trend of increasing underestimation with increasing intakes. Deattenuated and energy-adjusted Spearman rank correlations between the questionnaires and the WFR were in the range ρ=.25-.69, excluding sodium that was not statistically significant. Cross-classifications of quartiles of the 2 Meal-Q administrations placed 86% to 97% in the same/adjacent quartile. Intraclass correlation coefficients for energy-adjusted intakes were in the range of .50-.76.

CONCLUSIONS

With the exception of sodium, this validation study demonstrates Meal-Q and MiniMeal-Q to be useful methods for ranking micronutrient and fiber intake in epidemiological studies with Web-based data collection.

Socioeconomic variations in female fertility impairment: a study in a cohort of Portuguese mothers

OBJECTIVES

This study aimed to assess the association of socioeconomic conditions with female fertility impairment among women who delivered a live birth.

DESIGN

Cross-sectional analysis.

SETTING

Population-based birth cohort (Generation XXI) assembled in 2005/2006 from five public maternity units in Porto Metropolitan Region, Northern Portugal.

PARTICIPANTS

7472 women aged 18 or more with spontaneous conception and no male diagnosis of infertility were recruited and interviewed immediately after birth with structured questionnaires.

EXPOSURES OF INTEREST

Maternal education, occupation and income were recorded as proxy indicators of social conditions.

OUTCOME

Impaired female fertility, defined as women who had unsuccessfully tried to conceive for over a year.

DATA ANALYSIS

Multivariate logistic regression models were fitted to estimate the association between each socioeconomic indicator and impaired female fertility, stratified by previous pregnancy experience and adjusted for age, pregnancy planning and behavioural characteristics.

RESULTS

Among primigravidae, 7.7% (95% CI 6.8% to 8.6%) presented impaired fertility and the prevalence was 9.6% (95% CI 8.7% to 10.6%) in multigravidae. In crude analysis, we found women with impaired fertility to be older, less educated, more likely to have planned the current pregnancy and to be overweight/obese; they had similar levels of income or occupation. In multivariate models, a significant independent association between educational level and female fertility impairment remained among primigravidae (OR (95% CI) vs ≤6 schooling years: 7-9: 0.85 (0.54 to 1.34); 10-12: 0.34 (0.21 to 0.54); >12: 0.24 (0.14 to 0.40), ptrend<0.001) but not in multigravidae.

CONCLUSIONS

This study shows that education might be important in understanding female fertility impairment, particularly among first-time pregnant women. It also points out that the association is not totally explained by other sociodemographic and lifestyle characteristics that have been previously found to be important to disclose this relation.

Reproducibility and validity of a food frequency questionnaire among pregnant women in a Mediterranean area

BACKGROUND

Studies exploring the role of diet during pregnancy are still scarce, in part due to the complexity of measuring diet and to the lack of valid instruments. The aim of this study was to examine the reproducibility and validity (against biochemical biomarkers) of a semi-quantitative food frequency questionnaire (FFQ) in pregnant women.

METHODS

Participants were 740 pregnant women from a population-based birth cohort study in Valencia (INMA Study). We compared nutrient and food intakes from FFQs estimated for two periods of pregnancy (reproducibility), and compared energy-adjusted intake of several carotenoids, folate, vitamin B12, vitamin C and α-tocopherol of the FFQ in the first trimester with their concentration in blood specimens (validity).

RESULTS

Significant correlations for reproducibility were found for major food groups and nutrients but not for lycopene (r=0.06); the average correlation coefficients for daily intake were 0.51 for food groups and 0.61 for nutrients. For validity, statistically significant correlations were observed for vitamin C (0.18), α-carotene (0.32), β-carotene (0.22), lutein-zeaxantin (0.29) and β-cryptoxantin(0.26); non-significant correlations were observed for retinol, lycopene, α-tocopherol, vitamin B12 and folate (r≤0.12). When dietary supplement use was considered, correlations were substantially improved for folate (0.53) and to a lesser extent for vitamin B12 (0.12) and vitamin C (0.20).

CONCLUSION

This study supports that the FFQ has a good reproducibility for nutrient and food intake, and can provide a valid estimate of several important nutrients during pregnancy.

Repeatability and relative validity of a quantitative food-frequency questionnaire among French adults

BACKGROUND

A 50-item self-administered food frequency questionnaire (FFQ) was developed for French adults, to assess the intake of energy, 10 macronutrients, 11 vitamins, and 11 minerals, and to be used in the context of a medical consultation.

OBJECTIVE

To assess the repeatability and relative validity of this FFQ compared to a 7-day diet record (7-DR).

DESIGN

A total of 54 and 100 French adults were included in the repeatability and validation studies, respectively. Repeatability was assessed using two FFQs, the second carried out 3 weeks after the first. In the validation study, subjects first completed the FFQ, then the 7-DR the following week. Energy and nutrient intakes were compared using Pearson correlation. The degree of misclassification by the FFQ, compared to the 7-DR, was calculated by a contingency table of quintiles. Bland-Altman plots assessed the correlation between FFQ and 7-DR across the intake range.

RESULTS

Repeatability for intake, explored by Pearson correlation, was 0.62-0.90 (median: 0.81). Relative validity, as determined by Pearson correlation for the nutrient intake derived from the FFQ and 7-DR, was 0.36-0.80 (0.64). The FFQ tended to report higher fiber and micronutrient intake than 7-DR. Misclassification into opposite quintiles ranged 0-6% (1%), whereas classification into same or adjacent quintiles ranged 59-83% (74%). Bland-Altman plots showed good agreement for most nutrients across the range of intake.

CONCLUSION

This new FFQ showed a high repeatability and good relative validity, and thanks to its short length, should be a useful tool for rapidly evaluating the nutrient intake of French adults.