No abstract

Objective: To assess the relative validity of a semi-quantitative, web-based FFQ completed by female pregnancy planners in the Danish 'Snart Foraeldre' 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 Foraeldre' study who had completed the web-based FFQ were invited to participate in the validation study. Subjects: Participants in the 'Snart Foraeldre' 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.

Objective To investigate to what extent alcohol consumption affects female fecundability.Design Prospective cohort study.Setting Denmark, 1 June 2007 to 5 January 2016.Participants 6120 female Danish residents, aged 21-45 years, in a stable relationship with a male partner, who were trying to conceive and not receiving fertility treatment.Main outcome measures Alcohol consumption was self reported as beer (330 mL bottles), red or white wine (120 mL glasses), dessert wine (50 mL glasses), and spirits (20 mL) and categorized in standard servings per week (none, 1-3, 4-7, 8-13, and ≥14). Participants contributed menstrual cycles at risk until the report of pregnancy, start of fertility treatment, loss to follow-up, or end of observation (maximum 12 menstrual cycles). A proportional probability regression model was used to estimate fecundability ratios (cycle specific probability of conception among exposed women divided by that among unexposed women).Results 4210 (69%) participants achieved a pregnancy during follow-up. Median alcohol intake was 2.0 (interquartile range 0-3.5) servings per week. Compared with no alcohol consumption, the adjusted fecundability ratios for alcohol consumption of 1-3, 4-7, 8-13, and 14 or more servings per week were 0.97 (95% confidence interval 0.91 to 1.03), 1.01 (0.93 to 1.10), 1.01 (0.87 to 1.16) and 0.82 (0.60 to 1.12), respectively. Compared with no alcohol intake, the adjusted fecundability ratios for women who consumed only wine (≥3 servings), beer (≥3 servings), or spirits (≥2 servings) were 1.05 (0.91 to1.21), 0.92 (0.65 to 1.29), and 0.85 (0.61 to 1.17), respectively. The data did not distinguish between regular and binge drinking, which may be important if large amounts of alcohol are consumed during the fertile window.Conclusion Consumption of less than 14 servings of alcohol per week seemed to have no discernible effect on fertility. No appreciable difference in fecundability was observed by level of consumption of beer and wine.

PurposeCompliance with the Danish preconceptional folic acid (FA) recommendation – a daily supplement of 400 μg – is reported to be poor. Uncertainty remains, however, about the prevalence of compliers and health-related predictors of compliance in the preconceptional period.MethodsWe used self-reported baseline data from 5383 women, aged 18–40 years, enrolled in an Internet-based prospective cohort study of Danish pregnancy planners during 2007–2011. We estimated the prevalence proportions of FA or multivitamin (MV) use in relation to selected sociodemographic, lifestyle, reproductive, and medical characteristics. Multivariate binomial regression was used to obtain prevalence proportion differences with 95% confidence intervals for each level of study predictors, adjusted for all other predictors.ResultsOverall, 7.7% of women used FA supplements, 20.4% used MV supplements, 34.0% used both, 1.5% used other single vitamins or minerals, and 36.4% did not use any dietary supplements. The prevalence of FA or MV supplement use was higher among older women, women with higher education and income, and women with healthy lifestyle factors such as being a nonsmoker, nondrinker, physically active, maintaining a normal body mass index and having regular pap smears. Greater intercourse frequency and a history of spontaneous abortion were also positively associated with FA or MV supplement use. We found no clear association between use of FA or MV supplements and a diagnosis of hypertension, diabetes, thyroid disease, pelvic inflammatory disease, or chlamydia.ConclusionA large proportion of pregnancy planners do not use FA or MV supplements. Pregnancy planners with generally risky lifestyle behaviors are less likely to comply with the FA recommendation.

Background: Animal studies have shown that a high intake of galactose, a breakdown product of lactose, increases ovarian toxicity. Few epidemiologic studies, to our knowledge, have examined the association between dairy intake and fertility, and they have had conflicting findings. Objective: We prospectively evaluated dairy intake in relation to fecundability among women who were planning for pregnancy. Design: Data were derived from preconception cohort studies in Denmark (Snart Foraeldre) and North America [PRESTO (Pregnancy Study Online)] in which women completed a validated food-frequency questionnaire 10 d after enrollment. The dietary intake of dairy foods and their constituents was calculated based on reported frequencies, mean serving sizes, and standard recipes for mixed foods. Outcome data were updated every 8 wk for 12 mo or until reported conception. Analyses were restricted to 2426 women attempting pregnancy for #6 cycles at study entry. Fecundability ratios (FRs) and 95% CIs were estimated with the use of proportional probabilities regression models adjusted for potential confounders. Results: FRs for total dairy intake ($18 compared with ,7 servings/wk) were 1.37 (95% CI: 1.05, 1.78) among 1126 Snart Foraeldre participants and 1.04 (95% CI: 0.78, 1.38) among 1300 PRESTO participants (pooled FR: 1.11; 95% CI: 0.94, 1.31). The elevated FR for total dairy intake among Snart Foraeldre participants was limited to milk consumption and found only among women aged ,30 y. There was no clear association between low-or high-fat dairy intake and fecundability in either cohort. Although there was little evidence of an association between dietary intake of calcium, potassium, magnesium, or vitamin D and fecundability, a greater consumption of phosphorus and lactose was associated with slightly higher fecundability in both cohorts. Conclusions: Associations between dairy intake and fecundability were generally small and inconsistent across cohorts. Our findings do not support the hypotheses that a greater consumption of high-fat dairy improves fertility or that a greater consumption of lactose or low-fat dairy harms fertility.Am J Clin Nutr 2017;105:100-10.

Background Infertility is an important public health problem with few known modifiable risk factors. Dietary factors including folic acid have been associated with improved fertility, but the association between iron and fertility is understudied. One study among US nurses found a 40% lower risk of ovulatory infertility with higher intake of nonheme iron and iron supplements. Objectives The aim of this study was to determine the extent to which iron intake from diet and supplements reported on structured questionnaires is associated with fecundability. Methods We conducted parallel analyses that used data from 2 prospective cohort studies of pregnancy planners from Denmark (Snart Foraeldre; n = 1693) and North America (PRESTO; n = 2969) during 2013–2018. Follow-up comprised menstrual cycles at risk until pregnancy or censoring for fertility treatment, stopped trying to conceive, withdrawal, loss to follow-up, or 12 cycles of attempt. We used proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% CIs, adjusting for confounders. Results We found little association between dietary heme iron intake and fecundability in either cohort. The FR for nonheme iron intake (≥11 mg/d compared with <9 mg/day) was 1.11 for Snart Foraeldre participants (95% CI: 0.92, 1.34) and 1.01 for PRESTO participants (95% CI: 0.89, 1.14). The FR for iron-containing supplements was 1.01 in Snart Foraeldre (95% CI: 0.90, 1.13) and 1.19 in PRESTO (95% CI: 1.03, 1.38). In PRESTO, but not Snart Foraeldre, stronger positive associations were found for nonheme iron intake and iron supplement use among women with heavy menses or short menstrual cycles. Conclusions Overall, dietary intake of iron was not consistently associated with fecundability, although there was some evidence for a positive association among women with risk factors for iron deficiency. We also found a small positive association between supplemental iron intake and fecundability among North American, but not Danish, pregnancy planners.

Purpose To examine the association between folic acid (FA) supplementation obtained through either single FA tablets or multivitamins (MVs) and menstrual cycle characteristics among 5,386 women aged 18–40 years, enrolled in an Internet-based study of Danish women attempting pregnancy during 2007–2011. Methods In a cross-sectional study, we used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations of FA supplementation with menstrual cycle regularity, short (<27 days), long (30–33 days), and very long (≥34 days) cycle length, and duration and intensity of menstrual bleeding. Results Compared with non-use, FA supplementation was associated with reduced odds of short cycle length [OR=0.80, 95% CI: 0.68–0.94], and a trend towards increased odds of very long cycle length [OR=1.21, 95% CI: 0.87–1.68] compared with cycle length of 27–29 days. The inverse association with short cycle length was stronger among 18–30 year-old women [OR=0.68, 95% CI: 0.53–0.87], nulliparous women [OR=0.66, 95% CI: 0.52–0.84], and women who used both FA and MVs [OR=0.75, 95% CI: 0.60–0.95]. We found no clear association between FA supplementation and cycle regularity and duration and intensity of menstrual bleeding. Conclusion FA supplementation was inversely associated with short menstrual cycle length. This association was strongest among women aged 18–30 years, nulliparous women, and women who used both FA and MVs.

Salatrim had a modestly more suppressive effect on appetite than did a traditional fat. Gastrointestinal hormones did not seem to be involved.