Tracking of dietary patterns between pregnancy and 6 years post-pregnancy in a multiethnic Asian cohort: the Growing Up in Singapore Towards healthy Outcomes (GUSTO) study.

PURPOSE: Few studies have described adherence to dietary patterns over time in women of childbearing age. This study aims to describe, examine the stability and changes in dietary patterns between pregnancy and 6 years post-pregnancy and the sociodemographic and lifestyle factors influencing the adherence over time. METHODS: During pregnancy and at 6 years post-pregnancy, 24-h recalls and food frequency questionnaires were collected, respectively, from 709 women. Data on sociodemographic and lifestyle factors were collected via questionnaires. Dietary patterns were identified using principal component analysis and stability assessed using Pearson's correlation coefficients (r) and Cohen's weighted kappa (κ). Associations with sociodemographic characteristics were assessed by multiple logistic regression. RESULTS: The 'Fruits, Vegetables and Legumes' (FVL) and 'Seafood, Noodle, Soup' (SNS) patterns were identified at both time points, with low correlation for the dietary pattern z scores (r 0.2 and 0.3, respectively) and modest agreement in tertile assignment, suggesting poor stability. An 'unhealthy' pattern was only observed at 6 years post-pregnancy. Women who showed increased adherence to FVL pattern had higher educational attainment and exhibited healthy lifestyle behaviours. Women who had gestational diabetes during pregnancy were less likely to decrease adherence to FVL pattern over time. Women who adhered more closely to the 'unhealthy' pattern at 6 years post-pregnancy tended to be younger, of Malay ethnicity, had lower socioeconomic status, were less physically active and had additional pregnancies. CONCLUSIONS: Dietary habits of women became less healthy during the transition from pregnancy to 6 years post-pregnancy. However, results should be interpreted with caution due to the different dietary assessment tools used at the two time points.

Modifiable Risk Factor Score and Fecundability in a Preconception Cohort in Singapore.

Importance: Although multiple modifiable risk factors have been identified for reduced fecundability (defined as lower probability of conception within a menstrual cycle), no scoring system has been established to systematically evaluate fecundability among females who are attempting to conceive. Objective: To examine the association of a risk score based on 6 modifiable factors with fecundability, and to estimate the percentage reduction in incidence of nonconception if all study participants achieved a minimal risk score level. Design, Setting, and Participants: This population-based cohort study obtained data from the S-PRESTO (Singapore Preconception Study of Long-Term Maternal and Child Outcomes) prospective cohort study. Females of reproductive age who were trying to conceive were enrolled from February 2015 to October 2017 and followed for 1 year, ending in November 2018. Data were analyzed from March to May 2022. Exposures: A reduced fecundability risk score was derived by giving participants 1 point for each of the following factors: unhealthy body mass index, unhealthy diet, smoking, alcohol intake, folic acid supplement nonuser, and older maternal age. Total scores ranged from 0 to 6 and were classified into 5 levels: level 1 (score of 0 or 1), level 2 (score of 2), level 3 (score of 3), level 4 (score of 4), and level 5 (score of 5 or 6). Main Outcomes and Measures: Fecundability, measured by time to conception in cycles, was analyzed using discrete-time proportional hazards models with confounder adjustment. Results: A total of 937 females (mean [SD] age, 30.8 [3.8] years) were included, among whom 401 (42.8%) spontaneously conceived within 1 year of attempting conception; the median (IQR) number of cycles before conception was 4 (2-7). Compared with participants with a level 1 risk score, those with level 2, 3, 4, and 5 risk scores had reductions in fecundability of 31% (adjusted fecundability ratio [FR], 0.69; 95% CI, 0.54-0.88), 41% (FR, 0.59; 95% CI, 0.45-0.78), 54% (FR, 0.46; 95% CI, 0.31-0.69) and 77% (FR, 0.23; 95% CI, 0.07-0.73), respectively. Assessment of the population attributable fraction showed that all participants achieving a minimal (level 1) risk level would be associated with a reduction of 34% (95% CI, 30%-39%) in nonconception within a year. Conclusions and Relevance: Results of this study revealed the co-occurrence of multiple modifiable risk factors for lowered fecundability and a substantially higher conception rate among participants with no or minimal risk factors. The risk assessment scoring system proposed is a simple and potentially useful public health tool for mitigating risks and guiding those who are trying to conceive.

Prepregnancy adherence to plant-based diet indices and exploratory dietary patterns in relation to fecundability.

BACKGROUND: Modest associations have been reported between specific food groups or nutrients and fecundability [measured by time to pregnancy (TTP)]. Examining overall diets provides a more holistic approach towards understanding their associations with fecundability. It is not known whether plant-based diets indices or exploratory dietary patterns are associated with fecundability. OBJECTIVES: We examine the associations between adherence to 1) plant-based diet indices; and 2) exploratory dietary patterns and fecundability among women planning pregnancy. METHODS: Data were analyzed from the Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO) study. Prepregnancy diet was assessed using a semi-quantitative FFQ from which the overall, healthful, and unhealthful plant-based diet indices (oPDI, hPDI, and uPDI, respectively) were calculated. Exploratory dietary patterns were derived using factor analysis based on 44 predefined food groups. Participants were categorized into quintiles based on their dietary pattern scores. TTP (expressed in menstrual cycles) was ascertained within a year from the prepregnancy dietary assessment. Discrete-time proportional hazard models, adjusted for confounders, were used to estimate fecundability ratios (FRs) and 95% CIs, with FR > 1 indicating a shorter TTP. RESULTS: Among 805 women, 383 pregnancies were confirmed by ultrasound scans. Compared with women in the lowest quintile, those in the highest quintile of the uPDI had reduced fecundability (FR of Q5 compared with Q1, 0.65; 95% CI, 0.46-0.91; P trend, 0.009). Conversely, greater adherence to the hPDI was associated with increased fecundability (1.46; 95% CI, 1.02-2.07; P trend, 0.036). The oPDI was not associated with fecundability. Among the 3 exploratory dietary patterns, only greater adherence to the Fast Food and Sweetened Beverages (FFSB) pattern was associated with reduced fecundability (0.61; 95% CI, 0.40-0.91; P trend, 0.018). CONCLUSIONS: Greater adherence to the uPDI or the FFSB dietary pattern was associated with reduced fecundability among Asian women. Greater adherence to the hPDI may be beneficial for fecundability, though this requires confirmation by future studies.

Maternal Dietary Patterns and Birth Outcomes: A Systematic Review and Meta-Analysis.

Findings on the relations of maternal dietary patterns during pregnancy and risk of preterm birth and offspring birth size remain inconclusive. We aimed to systematically review and quantify these associations. We searched MEDLINE, Embase, CENTRAL, and CINAHL up to December 2017. Three authors independently conducted a literature search, study selection, data extraction, and quality assessment. Summary effect sizes were calculated with random effects models and studies were summarized narratively if results could not be pooled. We included 36 studies and pooled results from 25 observational studies (167,507 participants). Two common dietary patterns-"healthy" and "unhealthy"-were identified. Healthy dietary patterns-characterized by high intakes of vegetables, fruits, wholegrains, low-fat dairy, and lean protein foods-were associated with lower risk of preterm birth (OR for top compared with bottom tertile: 0.79; 95% CI: 0.68, 0.91; I2 = 32%) and a weak trend towards a lower risk of small-for-gestational-age (OR: 0.86; 95% CI: 0.73, 1.01; I2 = 34%). Only statistically data-driven healthy dietary patterns, and not dietary index-based patterns, were associated with higher birth weight (mean difference: 67 g; 95% CI: 37, 96 g; I2 = 75%). Unhealthy dietary patterns-characterized by high intakes of refined grains, processed meat, and foods high in saturated fat or sugar-were associated with lower birth weight (mean difference: -40 g; 95% CI: -61, -20 g; I2 = 0%) and a trend towards a higher risk of preterm birth (OR: 1.17; 95% CI: 0.99, 1.39; I2 = 76%). Data from observational studies indicate that greater adherence to healthy dietary patterns during pregnancy is significantly related to lower risk of preterm birth. No consistent associations with birth weight and small- or large-for-gestational-age were observed.