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Background Diet is increasingly recognized as an important determinant of human fertility, with most research focused on specific nutrients or food groups. However, there has been limited assessment of the effect of dietary patterns on fertility. Objectives We evaluated the association between 4 dietary patterns [the alternative Mediterranean Diet (aMed), the Healthy Eating Index-2010 (HEI-2010), the Danish Dietary Guidelines (DDGI), and the Dietary Inflammatory Index (DII)] and fecundability in 2 preconception cohorts of couples trying to conceive: SF (SnartForaeldre.dk) in Denmark and PRESTO (Pregnancy Study Online) in North America. Methods Participants completed a baseline questionnaire on sociodemographic, anthropometric, and lifestyle factors and, 10 d later, a validated cohort-specific FFQ. We used data from these respective FFQs to calculate adherence to each dietary pattern. Participants completed bimonthly follow-up questionnaires for ≤12 mo or until pregnancy, whichever came first. We restricted analyses to 3429 SF and 5803 PRESTO participants attempting pregnancy for ≤6 cycles at enrollment. We used proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% CIs, adjusting for potential confounders. Results Greater DII, indicative of a less anti-inflammatory diet (i.e. poorer diet quality), was associated with reduced fecundability in both SF and PRESTO (DII ≥ −1.5 compared with < −3.3: FR: 0.83; 95% CI: 0.71, 0.97 and FR: 0.82; 95% CI: 0.73, 0.93, respectively). In PRESTO, greater adherence to the aMed or to the HEI-2010 was associated with greater fecundability. In SF, there was no appreciable association between the aMed and fecundability, whereas greater adherence to the DDGI was associated with greater fecundability. Conclusions In prospective preconception cohort studies from Denmark and North America, higher-quality diets, including diets lower in inflammatory effects, were associated with greater fecundability. [ABSTRACT FROM AUTHOR]

Uterine leiomyomata (UL) are the leading indication for hysterectomy in the United States. Dietary supplementation with lycopene was associated with reduced size and incidence of oviduct leiomyoma in the Japanese quail. Two US prospective cohort studies of women reported little association between intake of lycopene, or other carotenoids, and UL incidence. However, these studies relied on self-reported physician-diagnosed UL, which is prone to misclassification. This study examines the association between dietary intake of carotenoids and UL incidence. Data were derived from the Study of the Environment, Lifestyle, and Fibroids, a prospective cohort study. Women completed self-administered baseline questionnaires on demographic characteristics, reproductive history, and lifestyle, including a 110-item validated food frequency questionnaire, from which dietary intakes of carotenoids—including alpha carotene, beta carotene, cryptoxanthin, lutein-zeaxanthin, and lycopene—and vitamin A were estimated. One thousand two hundred thirty Black women aged 23 to 35 years who did not have a previous diagnosis of UL, cancer, or autoimmune disease were eligible for enrollment (2010-2012). Participants were residents of the Detroit, MI, metropolitan area. Transvaginal ultrasound was used to assess UL at baseline and 20, 40, and 60 months of follow-up. Cox regression was used to estimate hazard ratios and 95% CIs, adjusted for energy intake, age at menarche, education, body mass index, parity, age at first birth, years since last birth, current use of oral contraceptives or progestin-only injectables, alcohol intake, and cigarette smoking. Among 1,230 women without prevalent UL at baseline, 301 incident UL cases during follow-up were identified. Intakes of lycopene, other carotenoids, and vitamin A were not appreciably associated with UL incidence. Hazard ratios comparing quartiles 2 (2,376 to 3,397 μg/day), 3 (3,398 to 4,817 μg/day), and 4 (≥4,818 μg/day) with quartile 1 (<2,376 μg/day) of lycopene intake were 1.03 (95% CI 0.72 to 1.47), 1.22 (95% CI 0.86 to 1.72), and 0.95 (95% CI 0.67 to 1.36), respectively. Study findings do not support the hypothesis that greater carotenoid intake is associated with reduced UL incidence. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]