Cohort profile: Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO)

Relation of preconception eating behaviours to dietary pattern trajectories and gestational weight gain from preconception to late pregnancy

Studies examining preconception eating behaviours with longitudinal dietary patterns from preconception to late pregnancy as well as gestational weight gain (GWG) are limited. We derived dietary pattern trajectories from preconception to late-pregnancy, and related preconception eating behaviours to these trajectories and GWG. Preconception eating behaviours were assessed using the Three-Factor Eating Questionnaire measuring cognitive restraint (CR) - conscious restriction of food intake, emotional eating (EE) - overeating in response to negative emotions, and uncontrolled eating (UE) - overeating with a feeling of lack of control. Dietary intakes were measured at preconception, 20-21 and 34-36 weeks' gestation with food frequency questionnaires. Dietary patterns were determined using factor analysis, and trajectories derived using group-based trajectory modelling. Inadequate and excessive GWG were defined according to Institute of Medicine guidelines based on weights at preconception and the last antenatal visit (median: 38 weeks' gestation). Two dietary patterns were derived: 'Fast Food, Fried Snacks and Desserts (FFD)' and 'Soup, Fish and Vegetables (SFV)'. Adherence trajectories from preconception to late-pregnancy were characterised as consistently high ("stable-high") and low ("stable-low"). Women with higher UE scores had higher odds of being in the "stable-high" trajectory (n = 34) of the FFD pattern [Odds Ratio (OR): 1.25, 95% Confidence Interval (CI): 1.03, 1.51], compared to "stable-low" (n = 260). Percentages of women with inadequate, adequate or excessive GWG were 21.7% (n = 70), 25.8% (n = 83), and 52.5% (n = 169), respectively; women with higher EE scores had a higher likelihood of excessive GWG [Relative Risk Ratio (RRR): 1.35, 95% CI: 1.02, 1.80], but this association was attenuated after adjusting for preconception body mass index. Eating behaviour interventions to improve dietary patterns among pregnant women may need to start as early as preconception, incorporating strategies to manage UE.

A machine-learning exploration of the exposome from preconception in early childhood atopic eczema, rhinitis and wheeze development

BACKGROUND

Most previous research on the environmental epidemiology of childhood atopic eczema, rhinitis and wheeze is limited in the scope of risk factors studied. Our study adopted a machine learning approach to explore the role of the exposome starting already in the preconception phase.

METHODS

We performed a combined analysis of two multi-ethnic Asian birth cohorts, the Growing Up in Singapore Towards healthy Outcomes (GUSTO) and the Singapore PREconception Study of long Term maternal and child Outcomes (S-PRESTO) cohorts. Interviewer-administered questionnaires were used to collect information on demography, lifestyle and childhood atopic eczema, rhinitis and wheeze development. Data training was performed using XGBoost, genetic algorithm and logistic regression models, and the top variables with the highest importance were identified. Additive explanation values were identified and inputted into a final multiple logistic regression model. Generalised structural equation modelling with maternal and child blood micronutrients, metabolites and cytokines was performed to explain possible mechanisms.

RESULTS

The final study population included 1151 mother-child pairs. Our findings suggest that these childhood diseases are likely programmed in utero by the preconception and pregnancy exposomes through inflammatory pathways. We identified preconception alcohol consumption and maternal depressive symptoms during pregnancy as key modifiable maternal environmental exposures that increased eczema and rhinitis risk. Our mechanistic model suggested that higher maternal blood neopterin and child blood dimethylglycine protected against early childhood wheeze. After birth, early infection was a key driver of atopic eczema and rhinitis development.

CONCLUSION

Preconception and antenatal exposomes can programme atopic eczema, rhinitis and wheeze development in utero. Reducing maternal alcohol consumption during preconception and supporting maternal mental health during pregnancy may prevent atopic eczema and rhinitis by promoting an optimal antenatal environment. Our findings suggest a need to include preconception environmental exposures in future research to counter the earliest precursors of disease development in children.

Holistic preconception care: Providing real-time guidance via a mobile app to optimise maternal and child health

Introduction

Preconception is a critical period to optimise gamete function and early placental development, essential for successful conception and long-term maternal-child health. However, there is a lack of preconception services and consequently, global fertility rates continue to fall and mothers embark on their pregnancy journey in poor health. There is an urgent need to implement a holistic community-level preconception care programme to optimise risk factors for poor fecundability and improve long-term maternal-child health.

Method

We reviewed current evidence on fecundability lifestyle risk factors, the efficacy of existing preconception interventions and the use of digital platforms for health optimisation, to create a new digital-based preconception intervention model that will be implemented via an app. We present the theory, content and mode of delivery of this holistic model targeting couples planning for pregnancy.

Results

We propose a new model featuring a user-friendly mobile app, which enables couples to self-assess fecundability risks through a personalised risk score that drives a tailored management plan. This tiered management provides anticipatory guidance supported by evidence-based recommen-dations, and promotes ongoing engagement for behavioural optimisation and specialist referrals as required. Based on the health belief model, this new model delivered with a mobile app seeks to shift couples' perceptions about their susceptibility and severity of subfertility, benefits of making a change and barriers to change.

Conclusion

Our proposed digital-based intervention model via a mobile app stands to enhance preconcep-tion care by providing personalised risk assessments, real-time feedback and tiered management to optimise preconception reproductive health of couples. This model forms a reference content framework for future preconception care intervention delivery.

Assessing preconception exposure to environmental chemicals and fecundity: Strategies, challenges, and research priorities

In 2022, approximately one out of six people globally experienced infertility at some point in their life. Environmental chemicals, particularly those with endocrine disrupting activity, may contribute to impaired fecundity and infertility. We review existing prospective cohort studies of environmental chemicals and fecundity, identify methodological challenges and biases, and outline future research priorities. Studies of preconception environmental chemical exposures and fecundity have occurred in US, Singapore, China and Denmark with recruitment as early as 1982-1986, as recent as 2015-2017 and sample sizes ranging from 99 to 936. Higher exposure to certain chemicals (e.g. heavy metals, perfluoroalkyl substances) was associated with longer time to pregnancy; yet the literature is scarce or nonexistent for many chemicals. Furthermore, prospective studies face challenges and potential biases related to recruiting participants prior to conception, measuring environmental chemicals during critical windows of exposure, and ascertaining when pregnancy occurred. Research priorities include expanding the scope of biomonitoring data collected during the preconception period, continuing to develop and validate analytic methods for self-sampled biospecimens in traditional and novel matrices, collecting data in male partners and investigating etiologic associations according to indicators of marginalization.

Neonatal Nucleus Accumbens Microstructure Modulates Individual Susceptibility to Preconception Maternal Stress in Relation to Externalizing Behaviors

OBJECTIVE

Maternal stress influences in utero brain development and is a modifiable risk factor for offspring psychopathologies. Reward circuitry dysfunction underlies various internalizing and externalizing psychopathologies. This study examined (1) the association between maternal stress and microstructural characteristics of the neonatal nucleus accumbens (NAcc), a major node of the reward circuitry, and (2) whether neonatal NAcc microstructure modulates individual susceptibility to maternal stress in relation to childhood behavioral problems.

METHOD

K-means longitudinal cluster analysis was performed to determine trajectories of maternal stress measures (Perceived Stress Scale [PSS], hair cortisol) from preconception to the third trimester. Neonatal NAcc microstructural measures (orientation density index [ODI] and intracellular volume fraction [ICVF]) were compared across trajectories. We then examined the interaction between maternal stress and neonatal NAcc microstructure on child internalizing and externalizing behaviors, assessed between ages 3 and 4 years.

RESULTS

Two trajectories of maternal stress magnitude ("low"/"high") were identified for both PSS (n = 287) and hair cortisol (n = 336). Right neonatal NAcc ODI (rNAcc-ODI) was significantly lower in "low" relative to "high" PSS trajectories (n = 77, p = .04). PSS at preconception had the strongest association with rNAcc-ODI (r = 0.293, p = .029). No differences in NAcc microstructure were found between hair cortisol trajectories. A significant interaction between preconception PSS and rNAcc-ODI on externalizing behavior was observed (n = 47, p = .047).

CONCLUSION

Our study showed that the preconception period contributes to in utero NAcc development, and that NAcc microstructure modulates individual susceptibility to preconception maternal stress in relation to externalizing problems.

Preconception maternal retinal arteriolar narrowing and fetal growth throughout pregnancy: A prospective cohort study

OBJECTIVE

To investigate the association between preconception maternal retinal arteriolar calibre and fetal growth.

DESIGN, SETTING AND POPULATION

A hospital-based, prospective preconception cohort including 369 women with a singleton live birth.

METHODS

We collected detailed information on sociodemographic status, pregnancy history and lifestyle, and performed retinal imaging at the preconception visit.

MAIN OUTCOME MEASURES

We retrieved medical records documenting fetal growth biometrics (e.g., abdominal circumference [AC], head circumference [HC], femur length [FL]) at 11-13, 18-21, 24-28, and 32-34 weeks throughout pregnancy. We then computed the z scores for all fetal growth biometrics from 14 weeks of gestation where data were available, referencing the INTERGROWTH-21st fetal growth chart. We used a linear mixed model to estimate the association between maternal preconception retinal arteriolar calibre and fetal growth biometrics z scores throughout pregnancy, with random intercept accounting for repeated measures within individuals. We then performed a multivariable linear regression of maternal preconception retinal arteriolar calibre and z score changes for all fetal growth biometrics between 24-28 weeks and 32-34 weeks of gestation, after full adjustment.

RESULTS

Maternal preconception generalised retinal arteriolar narrowing was consistently associated with a reduction in fetal AC z scores (-0.34; 95% CI -0.66 to -0.03) throughout pregnancy. In addition, women with preconception generalised retinal arteriolar narrowing tended to have significantly reduced z score changes in AC (-0.41; 95% CI -0.90 to -0.001) and fetal FL (-0.55; 95% CI -1.00 to -0.10) between 24-28 weeks and 32-34 weeks of gestation, respectively.

CONCLUSIONS

Our findings suggest that women with narrower preconception retinal arterioles had smaller fetuses, evidenced by reductions in AC and FL z score throughout pregnancy.

Growing Up in Singapore with allergies - Lessons learnt from the GUSTO & S-PRESTO cohorts

Healthcare systems across the world face major challenges due to allergic diseases, known to affect people of all ages. In Singapore, two prominent cohort studies, Growing Up in Singapore Towards healthy Outcomes (GUSTO) and the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO), have made notable advancements to our knowledge and understanding of allergic diseases. These cohorts, which comprised of healthy mother-infant dyads recruited from the healthy Singapore population, have shed light on the complex connections between factors influencing health in early life, preconception and pregnancy, on the pathogenesis of allergic disorders in offspring. GUSTO highlighted significant risk factors in antenatal and early life, such as maternal diet, health and lifestyle choices, as well as infant environmental influences, that contributed to the risk of allergic diseases in the Asian Singaporean population. It also identified differential patterns of allergic disease in comparison to other populations, particularly the role of the microbiome in predicting atopic outcomes. Meanwhile, S-PRESTO further explores the long-term maternal and child outcomes associated with preconception health. Findings seem to suggest that prevention of offspring allergic conditions can be achieved through optimizing maternal health and lifestyle choices before conception. Both studies underscore the significance of early life interventions, preconception health, and personalized approaches to effectively manage and prevent allergies. By leveraging the insights and promising findings from GUSTO and S-PRESTO, future work can drive development of preventative strategies and personalized interventions to reduce burden of allergic diseases in the Singapore population.

Common maternal health problems and their correlates in early post-partum mothers

BACKGROUND

Mothers experience a wide range of maternal health problems after childbirth, which in turn, affect their well-being and ability to care for their newborn. These problems may be influenced by factors such as mode of delivery or socio-economic status.

OBJECTIVE

This study aims to investigate the prevalence of common maternal health problems and their correlates in a public primary healthcare institution in Singapore.

DESIGN

This was a cross-sectional study, based on a self-administered questionnaire.

METHODS

A total of 373 mothers (mean age 31.9 years) who accompanied their infants for their 4- to 8-week development assessments at a public primary care clinic in Singapore completed a self-administered questionnaire from June 2021 to December 2021. The questionnaire assessed demographic factors, mode of delivery, number of children, number of individuals providing significant help, and the frequency of common physical and mental maternal health problems using a 5-point Likert-type scale.

RESULTS

The five most common maternal health problems were fatigue (77.7%), lower back pain (59.3%), Caesarean wound pain (54.3%), upper back pain (53.0%) and vaginal pain (41.2%). The prevalence of depression and anxiety was 22.0% and 11.3%, respectively. With respect to the symptoms' correlates, pain on passing urine was more frequent after assisted vaginal deliveries than all other forms of deliveries (all pairwise p < 0.01), and pain on passing motion was more frequent in vaginal deliveries than in Caesarean deliveries (all pairwise p < 0.05). Mothers having a larger number of children more frequently experienced headaches (β = 0.17, SE = 0.05, p = 0.002) and less frequently experienced breastfeeding difficulties (β = -0.28, SE = 0.08, p < 0.001).

CONCLUSION

Mothers experienced a high prevalence of maternal health problems in multiple domains during the first 8 weeks after childbirth. Mode of delivery and number of children were associated with increased prevalence of certain problems. Mothers' physical and mental well-being should be investigated early after delivery and addressed with adequate treatments and resources.

A fully convolutional neural network for comprehensive compartmentalization of abdominal adipose tissue compartments in MRI

BACKGROUND

Existing literature has highlighted structural, physiological, and pathological disparities among abdominal adipose tissue (AAT) sub-depots. Accurate separation and quantification of these sub-depots are crucial for advancing our understanding of obesity and its comorbidities. However, the absence of clear boundaries between the sub-depots in medical imaging data has challenged their separation, particularly for internal adipose tissue (IAT) sub-depots. To date, the quantification of AAT sub-depots remains challenging, marked by a time-consuming, costly, and complex process.

PURPOSE

To implement and evaluate a convolutional neural network to enable granular assessment of AAT by compartmentalization of subcutaneous adipose tissue (SAT) into superficial subcutaneous (SSAT) and deep subcutaneous (DSAT) adipose tissue, and IAT into intraperitoneal (IPAT), retroperitoneal (RPAT), and paraspinal (PSAT) adipose tissue.

MATERIAL AND METHODS

MRI datasets were retrospectively collected from Singapore Preconception Study for Long-Term Maternal and Child Outcomes (S-PRESTO: 389 women aged 31.4 ± 3.9 years) and Singapore Adult Metabolism Study (SAMS: 50 men aged 28.7 ± 5.7 years). For all datasets, ground truth segmentation masks were created through manual segmentation. A Res-Net based 3D-UNet was trained and evaluated via 5-fold cross-validation on S-PRESTO data (N = 300). The model's final performance was assessed on a hold-out (N = 89) and an external test set (N = 50, SAMS).

RESULTS

The proposed method enabled reliable segmentation of individual AAT sub-depots in 3D MRI volumes with high mean Dice similarity scores of 98.3%, 97.2%, 96.5%, 96.3%, and 95.9% for SSAT, DSAT, IPAT, RPAT, and PSAT respectively.

CONCLUSION

Convolutional neural networks can accurately sub-divide abdominal SAT into SSAT and DSAT, and abdominal IAT into IPAT, RPAT, and PSAT with high accuracy. The presented method has the potential to significantly contribute to advancements in the field of obesity imaging and precision medicine.

Longitudinal Analysis of Patterns and Correlates of Physical Activity and Sedentary Behavior in Women From Preconception to Postpartum: The Singapore Preconception Study of Long-Term Maternal and Child Outcomes Cohort

OBJECTIVE

Longitudinal changes in physical activity (PA) and sedentary behavior patterns from preconception to postpartum are not fully characterized. We examined changes and baseline sociodemographic/clinical correlates of PA and sedentary behavior in women from preconception to postpartum.

METHODS

The Singapore Preconception Study of Long-Term Maternal and Child Outcomes cohort recruited 1032 women planning pregnancy. Participants completed questionnaires at preconception, 34 to 36 weeks gestation, and 12 months postpartum. Repeated-measures linear regression models were used to analyze changes in walking, moderate to vigorous PA (MVPA), screen time, and total sedentary time, and to identify sociodemographic/clinical correlates associated with these changes.

RESULTS

Of the 373 women who delivered singleton live births, 281 provided questionnaires for all time points. Walking time increased from preconception to late pregnancy but decreased postpartum (adjusted means [95% CI]: 454 [333-575], 542 [433-651], and 434 [320-547] min/wk, respectively). Vigorous-intensity PA and MVPA decreased from preconception to late pregnancy but increased postpartum (vigorous-intensity PA: 44 [11-76], 1 [-3-5], and 11 [4-19] min/wk, MVPA: 273 [174-372], 165 [95-234], and 226 [126-325] min/wk, respectively). Screen time and total sedentary time remained consistent from preconception to pregnancy but decreased postpartum (screen: 238 [199-277], 244 [211-277], and 162 [136-189] min/d, total: 552 [506-598], 555 [514-596], and 454 [410-498] min/d, respectively). Individual characteristics of ethnicity, body mass index, employment, parity, and self-rated general health significantly influenced women's activity patterns.

CONCLUSION

During late pregnancy, walking time increased, while MVPA declined significantly, and partially returned to preconception levels postpartum. Sedentary time remained stable during pregnancy but decreased postpartum. The identified set of sociodemographic/clinical correlates underscores need for targeted strategies.

Time-to-conception and clinical pregnancy rate with a myo-inositol, probiotics, and micronutrient supplement: secondary outcomes of the NiPPeR randomized trial

OBJECTIVE

To determine whether a combined myo-inositol, probiotics and micronutrient nutritional supplement impacts time-to-natural-conception and clinical pregnancy rates.

DESIGN

Secondary outcomes of a double-blind randomized controlled trial.

SETTING

Community recruitment.

PATIENTS

Women aged 18 to 38 years planning to conceive in the United Kingdom, Singapore, and New Zealand, excluding those with diabetes mellitus or receiving fertility treatment.

INTERVENTION

A standard (control) supplement (folic acid, iron, calcium, iodine, β-carotene), compared with an intervention additionally containing myo-inositol, probiotics, and other micronutrients (vitamins B2, B6, B12, D, zinc).

MAIN OUTCOME MEASURES

Number of days between randomization and estimated date of natural conception of a clinical pregnancy, as well as cumulative pregnancy rates at 3, 6, and 12 months.

RESULTS

Of 1729 women randomized, 1437 (83%; intervention, n=736; control, n=701) provided data. Kaplan-Meier curves of conception were similar between intervention and control groups; the time at which 20% achieved natural conception was 90.5 days (95% confidence interval: 80.7, 103.5) in the intervention group compared with 92.0 days (76.0, 105.1) in the control group. Cox's proportional hazard ratios (HRs) comparing intervention against control for cumulative achievement of pregnancy (adjusted for site, ethnicity, age, body mass index, and gravidity) were similar at 3, 6, and 12 months. Among both study groups combined, overall time-to-conception lengthened with higher preconception body mass index, and was longer in non-White than in White women. Among women who were overweight the intervention shortened time-to-conception compared with control regardless of ethnicity (12-month HR=1.47 [1.07, 2.02], P=.016; 20% conceived by 84.5 vs. 117.0 days) and improved it to that comparable to nonoverweight/nonobese women (20% conceived by 82.1 days). In contrast, among women with obesity, time-to-conception was lengthened with intervention compared with control (12-month HR=0.69 [0.47, 1.00]; P=.053; 20% conceived by 132.7 vs. 108.5 days); an effect predominantly observed in non-White women with obesity.

CONCLUSIONS

Time-to-natural-conception and clinical pregnancy rates within a year were overall similar in women receiving the intervention supplement compared with control. Overweight women had a longer time-to-conception but there was suggestion that the supplement may shorten their time-to-conception to that comparable to the nonoverweight/nonobese women. Further studies are required to confirm this.

CLINICAL TRIAL REGISTRATION NUMBER

clinicaltrials.gov (NCT02509988).

Exposure to perfluoroalkyl substances and women's fertility outcomes in a Singaporean population-based preconception cohort

OBJECTIVES

Experimental models have demonstrated a link between exposure to perfluoroalkyl substances (PFAS) and decreased fertility and fecundability; however, human studies are scarce. We assessed the associations between preconception plasma PFAS concentrations and fertility outcomes in women.

METHODS

In a case-control study nested within the population-based Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO), we measured PFAS in plasma collected in 2015-2017 from 382 women of reproductive age trying to conceive. Using Cox proportional hazards regression (fecundability ratios [FRs]) and logistic regression (odds ratios [ORs]) models, we assessed the associations of individual PFAS with time-to-pregnancy (TTP), and the likelihoods of clinical pregnancy and live birth, respectively, over one year of follow-up, adjusting for analytical batch, age, education, ethnicity, and parity. We used Bayesian weighted quantile sum (BWQS) regression to assess the associations of the PFAS mixture with fertility outcomes.

RESULTS

We found a 5-10 % reduction in fecundability per quartile increase of exposure to individual PFAS (FRs [95 % CIs] for clinical pregnancy = 0.90 [0.82, 0.98] for PFDA; 0.88 [0.79, 0.99] for PFOS; 0.95 [0.86, 1.06] for PFOA; 0.92 [0.84, 1.00] for PFHpA). We observed similar decreased odds of clinical pregnancy (ORs [95 % CIs] = 0.74 [0.56, 0.98] for PFDA; 0.76 [0.53, 1.09] for PFOS; 0.83 [0.59, 1.17] for PFOA; 0.92 [0.70, 1.22] for PFHpA) and live birth per quartile increases of individual PFAS and the PFAS mixture (ORs [95 % CIs] = 0.61 [0.37, 1.02] for clinical pregnancy, and 0.66 [0.40, 1.07] for live birth). Within the PFAS mixture, PFDA followed by PFOS, PFOA, and PFHpA were the biggest contributors to these associations. We found no evidence of association for PFHxS, PFNA, and PFHpS and the fertility outcomes examined.

CONCLUSIONS

Higher PFAS exposures may be associated with decreased fertility in women. The potential impact of ubiquitous PFAS exposures on infertility mechanisms requires further investigation.

Preconception sleep quality moderates the association between preconception hair cortisol levels and mental health in pregnant women

BACKGROUND

Poor sleep quality may elevate cortisol levels and affect prenatal mental health through altered HPA axis functioning. This study aims to examine whether subjective sleep quality during preconception moderates the association between preconception hair cortisol levels and mental health from preconception to pregnancy trimesters.

METHODS

Women from a prospective cohort study completed the Pittsburgh Sleep Quality Index (PSQI), the Edinburgh Postnatal Depression Scale (EPDS), and the State-Trait Anxiety Inventory (STAI) questionnaires during preconception (T0) and at each pregnancy trimesters (T1, T2, and T3). We analyzed 266 of these women who conceived and had fully completed measures at preconception for hair cortisol, sleep quality and either EPDS or STAI-state. Changes in EPDS and STAI-state scores were derived (i.e., T1-T0, T2-T0, T3-T0). Johnson-Neyman technique identified PSQI scores with significant moderation of cortisol on mental health.

RESULTS

After adjusting for potential covariates, there was a significant positive correlation between preconception hair cortisol levels and depressive symptom at the second trimester (r_s (144) = 0.22, p = 0.008), but not the first and third trimesters (all p_s > 0.05). The positive association between preconception hair cortisol and change in depressive symptoms between third trimester and preconception was significant only among women with poor preconception sleep quality (PSQI ≥ 7).

LIMITATIONS

Sleep quality and prenatal mood were derived from self-reported questionnaires, which may be more susceptible to bias.

CONCLUSIONS

The positive association between preconception hair cortisol and change in prenatal depressive symptoms is significant among women who reported poor sleep quality during preconception. Improving preconception sleep quality can potentially mitigate the association between preconception hair cortisol and depressive symptoms during pregnancy.

Exploring preconception signatures of metabolites in mothers with gestational diabetes mellitus using a non-targeted approach

BACKGROUND

Metabolomic changes during pregnancy have been suggested to underlie the etiology of gestational diabetes mellitus (GDM). However, research on metabolites during preconception is lacking. Therefore, this study aimed to investigate distinctive metabolites during the preconception phase between GDM and non-GDM controls in a nested case-control study in Singapore.

METHODS

Within a Singapore preconception cohort, we included 33 Chinese pregnant women diagnosed with GDM according to the IADPSG criteria between 24 and 28 weeks of gestation. We then matched them with 33 non-GDM Chinese women by age and pre-pregnancy body mass index (ppBMI) within the same cohort. We performed a non-targeted metabolomics approach using fasting serum samples collected within 12 months prior to conception. We used generalized linear mixed model to identify metabolites associated with GDM at preconception after adjusting for maternal age and ppBMI. After annotation and multiple testing, we explored the additional predictive value of novel signatures of preconception metabolites in terms of GDM diagnosis.

RESULTS

A total of 57 metabolites were significantly associated with GDM, and eight phosphatidylethanolamines were annotated using HMDB. After multiple testing corrections and sensitivity analysis, phosphatidylethanolamines 36:4 (mean difference β: 0.07; 95% CI: 0.02, 0.11) and 38:6 (β: 0.06; 0.004, 0.11) remained significantly higher in GDM subjects, compared with non-GDM controls. With all preconception signals of phosphatidylethanolamines in addition to traditional risk factors (e.g., maternal age and ppBMI), the predictive value measured by area under the curve (AUC) increased from 0.620 to 0.843.

CONCLUSIONS

Our data identified distinctive signatures of GDM-associated preconception phosphatidylethanolamines, which is of potential value to understand the etiology of GDM as early as in the preconception phase. Future studies with larger sample sizes among alternative populations are warranted to validate the associations of these signatures of metabolites and their predictive value in GDM.

Plasma lipidomic profiling reveals metabolic adaptations to pregnancy and signatures of cardiometabolic risk: a preconception and longitudinal cohort study

BACKGROUND

Adaptations in lipid metabolism are essential to meet the physiological demands of pregnancy and any aberration may result in adverse outcomes for both mother and offspring. However, there is a lack of population-level studies to define the longitudinal changes of maternal circulating lipids from preconception to postpartum in relation to cardiometabolic risk factors.

METHODS

LC-MS/MS-based quantification of 689 lipid species was performed on 1595 plasma samples collected at three time points in a preconception and longitudinal cohort, Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO). We mapped maternal plasma lipidomic profiles at preconception (N = 976), 26-28 weeks' pregnancy (N = 337) and 3 months postpartum (N = 282) to study longitudinal lipid changes and their associations with cardiometabolic risk factors including pre-pregnancy body mass index, body weight changes and glycaemic traits.

RESULTS

Around 56% of the lipids increased and 24% decreased in concentration in pregnancy before returning to the preconception concentration at postpartum, whereas around 11% of the lipids went through significant changes in pregnancy and their concentrations did not revert to the preconception concentrations. We observed a significant association of body weight changes with lipid changes across different physiological states, and lower circulating concentrations of phospholipids and sphingomyelins in pregnant mothers with higher pre-pregnancy BMI. Fasting plasma glucose and glycated haemoglobin (HbA1c) concentrations were lower whereas the homeostatic model assessment of insulin resistance (HOMA-IR), 2-h post-load glucose and fasting insulin concentrations were higher in pregnancy as compared to both preconception and postpartum. Association studies of lipidomic profiles with these glycaemic traits revealed their respective lipid signatures at three physiological states. Assessment of glycaemic traits in relation to the circulating lipids at preconception with a large sample size (n = 936) provided an integrated view of the effects of hyperglycaemia on plasma lipidomic profiles. We observed a distinct relationship of lipidomic profiles with different measures, with the highest percentage of significant lipids associated with HOMA-IR (58.9%), followed by fasting insulin concentration (56.9%), 2-h post-load glucose concentration (41.8%), HbA1c (36.7%), impaired glucose tolerance status (31.6%) and fasting glucose concentration (30.8%).

CONCLUSIONS

We describe the longitudinal landscape of maternal circulating lipids from preconception to postpartum, and a comprehensive view of trends and magnitude of pregnancy-induced changes in lipidomic profiles. We identified lipid signatures linked with cardiometabolic risk traits with potential implications both in pregnancy and postpartum life. Our findings provide insights into the metabolic adaptations and potential biomarkers of modifiable risk factors in childbearing women that may help in better assessment of cardiometabolic health, and early intervention at the preconception period.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03531658.

Maternal preconception circulating blood biomarker mixtures, child behavioural symptom scores and the potential mediating role of neonatal brain microstructure: the S-PRESTO cohort

Human brain development starts in the embryonic period. Maternal preconception nutrition and nutrient availability to the embryo may influence brain development at this critical period following conception and early cellular differentiation, thereby affecting offspring neurodevelopmental and behavioural disorder risk. However, studying this is challenging due to difficulties in characterizing preconception nutritional status and few studies have objective neurodevelopmental imaging measures in children. We investigated the associations of maternal preconception circulating blood nutrient-related biomarker mixtures (~15 weeks before conception) with child behavioural symptoms (Child Behaviour Checklist (CBCL), aged 3 years) within the Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO) study. The CBCL preschool form evaluates child behaviours based on syndrome scales and Diagnostic and Statistical Manual of Mental Disorders (DSM) oriented scales. These scales consist of internalizing problems, externalizing problems, anxiety problems, pervasive developmental problems, oppositional defiant, etc. We applied data-driven clustering and a method for modelling mixtures (Bayesian kernel machine regression, BKMR) to account for complex, non-linear dependencies between 67 biomarkers. We used effect decomposition analyses to explore the potential mediating role of neonatal (week 1) brain microstructure, specifically orientation dispersion indices (ODI) of 49 cortical and subcortical grey matter regions. We found that higher levels of a nutrient cluster including thiamine, thiamine monophosphate (TMP), pyridoxal phosphate, pyridoxic acid, and pyridoxal were associated with a higher CBCL score for internalizing problems (posterior inclusion probability (PIP) = 0.768). Specifically, thiamine independently influenced CBCL (Conditional PIP = 0.775). Higher maternal preconception thiamine level was also associated with a lower right subthalamic nucleus ODI (P-value = 0.01) while a lower right subthalamic nucleus ODI was associated with higher CBCL scores for multiple domains (P-value < 0.05). One potential mechanism is the suboptimal metabolism of free thiamine to active vitamin B1, but additional follow-up and replication studies in other cohorts are needed.

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.

Joint modelling of mental health markers through pregnancy: a Bayesian semi-parametric approach

Maternal depression and anxiety through pregnancy have lasting societal impacts. It is thus crucial to understand the trajectories of its progression from preconception to postnatal period, and the risk factors associated with it. Within the Bayesian framework, we propose to jointly model seven outcomes, of which two are physiological and five non-physiological indicators of maternal depression and anxiety over time. We model the former two by a Gaussian process and the latter by an autoregressive model, while imposing a multidimensional Dirichlet process prior on the subject-specific random effects to account for subject heterogeneity and induce clustering. The model allows for the inclusion of covariates through a regression term. Our findings reveal four distinct clusters of trajectories of the seven health outcomes, characterising women's mental health progression from before to after pregnancy. Importantly, our results caution against the loose use of hair corticosteroids as a biomarker, or even a causal factor, for pregnancy mental health progression. Additionally, the regression analysis reveals a range of preconception determinants and risk factors for depressive and anxiety symptoms during pregnancy.

Effects of an integrated mobile health lifestyle intervention among overweight and obese women planning for pregnancy in Singapore: protocol for the single-arm healthy early life moments in Singapore (HELMS) study

INTRODUCTION

Changes in social and lifestyle factors have led to increasing rates of metabolic and mental health problems. We hypothesise that a transformation of the current maternal and child health system is required to deliver interventions that effectively promote a good start to life in populations at risk of metabolic and mental health problems. We describe a single-arm implementation study 'Healthy Early Life Moments in Singapore', which aims to examine whether an integrated lifestyle intervention initiated at preconception and continuing throughout pregnancy and postpartum periods can improve the metabolic and mental health of overweight and obese women, and improve early child growth.

METHODS AND ANALYSIS

This single-centre implementation trial is conducted at KK Women's and Children's Hospital, Singapore. The trial aims to recruit 500 women, aged 21-40 years with a body mass index of 25-40 kg/m² who plan to get pregnant, with interventions delivered before conception, until 18 months postdelivery. Primary outcomes comprise pregnancy rate, maternal metabolic and mental health status. Secondary outcomes include maternal reproductive health, pregnancy outcomes and offspring growth. The intervention will be delivered using a mobile health application, to provide anticipatory guidance, raise awareness and guide goal-setting on lifestyle behaviours that include diet, physical activity, mental wellness and sleep hygiene from preconception to postpartum. Women who conceive within 1 year of recruitment will be followed through pregnancy and studied with their infants at six-time points during the first 18 months of life. Questionnaires, anthropometric measurements and multiple biosamples will be collected at each visit.

ETHICS AND DISSEMINATION

The study has been approved by the Centralised Institutional Review Board of SingHealth (2021/2247). Written informed consent will be obtained from all participants. The findings will be published in peer-reviewed journals and disseminated to national and international policy makers.

TRIAL REGISTRATION NUMBER

NCT05207059.

Dietary Supplement Intake and Fecundability in a Singapore Preconception Cohort Study

Subfertility is a global problem affecting millions worldwide, with declining total fertility rates. Preconception dietary supplementation may improve fecundability, but the magnitude of impact remains unclear. This prospective cohort study aimed to examine the association of preconception micronutrient supplements with fecundability, measured by time to pregnancy (TTP). The study was conducted at KK Women's and Children's Hospital, Singapore, between February 2015 and October 2017, on 908 women aged 18-45 years old, who were trying to conceive and were enrolled in the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO). Baseline sociodemographic characteristics and supplement intake were collected through face-to-face interviews. The fecundability ratio (FR) was estimated using discrete-time proportional hazard modelling. Adjusting for potentially confounding variables, folic acid (FA) (FR 1.26, 95% confidence interval 1.03-1.56) and iodine (1.28, 1.00-1.65) supplement users had higher fecundability compared to non-users. Conversely, evening primrose oil supplement users had lower fecundability (0.56, 0.31-0.99) than non-users. In this study, preconception FA and iodine supplementation were associated with shortened TTP, while evening primrose oil use was associated with longer TTP. Nonetheless, the association between supplement use and the magnitude of fecundability changes will need to be further confirmed with well-designed randomised controlled trials.

Retinal microvasculature and risk of spontaneous abortion in multiethnic Southeast Asian women

OBJECTIVE

To better understand the underlying pathogenesis of spontaneous abortion that affects 10%-20% of recognized pregnancies. We used retinal imaging to study the role of systemic microvasculature and the risk of spontaneous abortion.

DESIGN

A prospective multiethnic preconception cohort study conducted in Singapore.

SETTING

Hospital-based.

PATIENT(S)

A total of 1,032 Southeast Asian women who intended to conceive naturally were screened at study entry, among which 480 women spontaneously conceived within the 12-month observation period. After excluding 24 women who were lost to follow-up, we calculated the spontaneous abortion rate among 456 women. Further, we included 379 women for the final association analysis because 63 women did not undergo preconception retinal imaging examination and 14 had other types of pregnancy loss instead of spontaneous abortion.

INTERVENTION(S)

Trained photographers performed retinal examination using a 45-degree nonmydriatic retinal camera at study entry during the preconception screening. Using a semiautomated, computer-based program, we assessed quantitative retinal microvascular measurements, including caliber, fractal dimension, curvature tortuosity, and branching angle. Clinical research coordinators collected information on sociodemographic status, menstrual characteristics, and lifestyle, and assessed blood pressure and anthropometry at study entry.

MAIN OUTCOME MEASURE(S)

We performed a modified Poisson regression model to estimate the relative risk (RR) and 95% confidence interval (CI) for each retinal microvascular feature and its association with spontaneous abortion after adjusting for major confounders such as maternal prepregnancy, body mass index, and previous pregnancy loss history.

RESULT(S)

We reported a spontaneous abortion rate of 13.4% (61 out of 456). Among all retinal microvascular features, retinal arteriolar caliber, retinal arteriolar, and venular curvature tortuosity were associated with a high risk of incident spontaneous abortion. In the regression model, per SD increase in retinal curvature tortuosity was associated with a 25%-34% increased risk of incident spontaneous abortion (arteriolar: unadjusted RR, 1.29 [95% CI, 1.06-1.56] and adjusted RR, 1.26 [1.04-1.53]; venule: unadjusted RR, 1.30 [1.08-1.55] and adjusted RR, 1.34 [1.09-1.64]).

CONCLUSION(S)

Our prospective cohort observed an increased risk of spontaneous abortion among Asian women with more tortuous retinal vessels assessed during the preconception phase. Our results indicate a role of vascular inflammatory and oxidative stress in the pathogenesis of spontaneous abortion.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT03531658.

A Golden Thread approach to transforming Maternal and Child Health in Singapore

Maternal and child health (MCH) in Singapore is entering a new phase, with challenges different to those faced 50 years ago. The advancement of medical technologies and access to MCH resources have led to a dramatic fall in maternal and infant mortality rates. However, there has been a steep rise in the rates of obesity and related metabolic diseases. Alongside this is an emerging mental wellness challenge, with one in ten women experience depression across pre-, during and post-pregnancy. Maternal obesity and mental disorders before and during pregnancy not only increase a woman's risk of pregnancy complications, but also result in increased risks in the offspring of childhood obesity, behavioral disorders and later life metabolic disease, catalyzing vicious cycles of disease. Thus, there is a pressing need to transform the current MCH system to address a burgeoning metabolic and mental health challenge for Singapore. Initiating interventions during preconception and continuing into the postpartum has the potential to confer long-term maternal-child benefits, promoting virtuous cycles of health. However, the current MCH system emphasizes antenatal care and lacks focus on the equally, if not more important, preconception, postpartum and inter-pregnancy stages. We describe a new model-of-care framework that integrates a life-course approach to health across preconception, pregnancy and postpartum phases, with the social-ecological model comprising individual, interpersonal, institutional, community and policy as the major targets for health promotion interventions. This "golden thread" approach is being established at the Singapore KK Women's and Children's Hospital (KKH), to address both metabolic and mental health challenges to achieve the goal of a thriving, healthy nation. This new model-of-care is set up in KKH as a pilot program known as Healthy Early Life Moments in Singapore (HELMS). HELMS will reach out to women planning to conceive through coordinated interventions across preconception, pregnancy and postpartum periods. A mobile health platform is being developed to facilitate interventions and engage participants in the program through a digital, personalized and interactive approach. This new model-of-care is designed to secure a population with healthy life cycles, by influencing each life-course, early-in-life, to provide the best start for generations to come.

Cohort profile: Anhui Maternal-Child Health Study in China

PURPOSE

The Anhui Maternal-Child Health Study (AMCHS) aims to examine determinants of reproduction, pregnancy and postpartum maternal and child health outcomes in Chinese women who received assisted reproductive technology (ART).

STUDY DESIGN AND PARTICIPANTS

AMCHS is an ongoing cohort study starting from May 2017. AMCHS recruits participants from all couples who sought ART treatment in the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China. The participants are interviewed to document baseline sociodemography, lifestyles, dietary intake and environmental exposure. Their clinical characteristics are obtained from hospital records. Samples of blood, follicular fluid and semen are collected at the clinic. Participants receive a standard long pituitary downregulation or a short protocol with an antagonist for the treatment. They are followed up from preconception to delivery, or discontinuation of ART treatment. Details of their children's health are documented through a questionnaire focusing on developmental status and anthropometry measurement.

FINDINGS TO DATE

Until April 2021, AMCHS had recruited 2042 couples in the study. 111 women withdrew from the study and 19 failed to retrieve oocytes. Among the 1475 confirmed pregnancies, 146 had miscarriages or terminated their pregnancies, 9 had stillbirths and 263 were ongoing pregnancies. The implantation failure increased with maternal age; adjusted OR was 1.43 (95% CI 1.16 to 1.77) in the age of 31-35 years, 1.97 (95% CI 1.46 to 2.66) in 35-39 years and 6.52 (95% CI 3.35 to 12.68) in ≥40 years compared with those aged 20-30 years. Among the 1057 couples with successful ART who were followed up for delivering babies, 576 had their children examined at age 30-42 days, 459 at 6 months and 375 at 12 months.

FUTURE PLANS

The AMCHS will identify comprehensive risk factors for poor ART outcomes and explore potential interaction effects of multiple factors including sociopsychological aspects of environmental exposure, dietary intake and genetics on maternal and child health.

The current situation and future directions for the study on time-to-pregnancy: a scoping review

Introduction

As problems associated with infertility and population aging increase, there is a growing interest in the factors that cause a decline in human fertility. Time-to-pregnancy (TTP) is a good indicator with which to reflect human fecundability. Here, we present a comprehensive overview of this topic.

Methods

Relevant qualitative and quantitative studies were identified by searching the Web of science and PubMed electronic databases. We included all literature, written in English, from inception to the 10th April 2021 providing the focus was on TTP. We conducted a narrative synthesis using thematic analysis.

Results

Traditional TTP-related study protocols include prospective and retrospective cohorts that provide a wealth of data to reveal potential influences on TTP. Thus far, a variety of factors have been shown to be associated with TTP in couples preparing for pregnancy, including basic demographic characteristics, menstrual status, chronic disease status, environmental endocrine disruptor exposure, and lifestyles. However, there are inevitable epidemiological bias in the existing studies, including recall bias, selection bias and measurement bias. Some methodological advances have brought new opportunities to TTP research, which make it possible to develop precision interventions for population fertility. Future TTP studies should take advantage of artificial intelligence, machine learning, and high-throughput sequencing technologies, and apply medical big data to fully consider and avoid possible bias in the design.

Conclusion

There are many opportunities and future challenges for TTP related studies which would provide a scientific basis for the “precise health management” of the population preparing for pregnancy.

As the problems of infertility and population aging increase, there is a growing interest in the factors that cause a decline in human fertility. Time-to-pregnancy (TTP) is a good indicator with which to reflect human fecundability, and a longer TTP is known to reflect a reduction in fertility. Many original studies, with different designs, have used TTP to explore the factors that might influence fertility, including basic demographic characteristics, chronic disease status, environmental endocrine disruptor exposure, and lifestyles. However, much of the existing evidence is inconsistent and limited by various types of bias. This review provides a synopsis of recent TTP studies, and highlights new opportunities and future challenges.

Automated Machine Learning (AutoML)-Derived Preconception Predictive Risk Model to Guide Early Intervention for Gestational Diabetes Mellitus

The increasing prevalence of gestational diabetes mellitus (GDM) is contributing to the rising global burden of type 2 diabetes (T2D) and intergenerational cycle of chronic metabolic disorders. Primary lifestyle interventions to manage GDM, including second trimester dietary and exercise guidance, have met with limited success due to late implementation, poor adherence and generic guidelines. In this study, we aimed to build a preconception-based GDM predictor to enable early intervention. We also assessed the associations of top predictors with GDM and adverse birth outcomes. Our evolutionary algorithm-based automated machine learning (AutoML) model was implemented with data from 222 Asian multi-ethnic women in a preconception cohort study, Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO). A stacked ensemble model with a gradient boosting classifier and linear support vector machine classifier (stochastic gradient descent training) was derived using genetic programming, achieving an excellent AUC of 0.93 based on four features (glycated hemoglobin A1c (HbA1c), mean arterial blood pressure, fasting insulin, triglycerides/HDL ratio). The results of multivariate logistic regression model showed that each 1 mmol/mol increase in preconception HbA1c was positively associated with increased risks of GDM (p = 0.001, odds ratio (95% CI) 1.34 (1.13-1.60)) and preterm birth (p = 0.011, odds ratio 1.63 (1.12-2.38)). Optimal control of preconception HbA1c may aid in preventing GDM and reducing the incidence of preterm birth. Our trained predictor has been deployed as a web application that can be easily employed in GDM intervention programs, prior to conception.

Metabolic health status and fecundability in a Singapore preconception cohort study

BACKGROUND

Obesity compromises metabolic health and female fertility, yet not all obese women are similar in metabolic status. The extent to which fecundability is influenced by the metabolic health status of women who are overweight or obese before conception is unknown.

OBJECTIVE

This study aimed to: (1) determine the metabolic health status, and (2) examine the association between metabolic health status and fecundability of overweight and obese women trying to conceive in the Singapore PREconception Study of long-Term maternal and child Outcomes cohort study.

STUDY DESIGN

We conducted a prospective preconception cohort study of Asian women (Chinese, Malay, and Indian) aged 18 to 45 years trying to conceive who were treated from 2015 to 2017 in KK Women's and Children's Hospital in Singapore (n=834). We defined women to have metabolically unhealthy status if they: (1) met 3 or more modified Joint Interim Statement metabolic syndrome criteria; or (2) had homeostasis model assessment-insulin resistance index ≥2.5. Body mass index was categorized as normal (18.5-22.9 kg/m2), overweight (23-27.4 kg/m2), or obese (≥27.5 kg/m2) on the basis of cutoff points for Asian populations. Fecundability was measured by time to pregnancy in menstrual cycles within a year of enrolment. Discrete-time proportional hazards models were used to estimate fecundability odds ratios, with adjustment for confounders and accounting for left truncation and right censoring.

RESULTS

Of 232 overweight women, 28 (12.1%) and 25 (10.8%) were metabolically unhealthy by metabolic syndrome ≥3 criteria and homeostasis model assessment-insulin resistance ≥2.5, respectively. Of 175 obese women, 54 (30.9%) and 93 (53.1%) were metabolically unhealthy by metabolic syndrome ≥3 criteria and homeostasis model assessment-insulin resistance ≥2.5, respectively. Compared with metabolically healthy normal-weight women, lower fecundability was observed in metabolically unhealthy overweight women on the basis of metabolic syndrome criteria (fecundability odds ratios, 0.38 [95% confidence interval, 0.15-0.92]) and homeostasis model assessment-insulin resistance (fecundability odds ratios, 0.68 [95% confidence interval, 0.33-1.39]), with metabolic syndrome criteria showing a stronger association. Metabolically unhealthy obese women showed lower fecundability than the healthy normal-weight reference group by both metabolic syndrome (fecundability odds ratios, 0.35; 95% confidence interval, 0.17-0.72) and homeostasis model assessment-insulin resistance criteria (fecundability odds ratios, 0.43; 95% confidence interval, 0.26-0.71). Reduced fecundability was not observed in overweight or obese women who showed healthy metabolic profiles by either definition.

CONCLUSION

Overweight or obesity was not synonymous with having metabolic syndrome or insulin resistance. In our preconception cohort, metabolically unhealthy overweight and obese women showed reduced fecundability, unlike their counterparts who were metabolically healthy. These findings suggest that metabolic health status, rather than simply being overweight and obese per se, plays an important role in fecundability.

Prevalence, risk factors and parental perceptions of gastroesophageal reflux disease in Asian infants in Singapore

INTRODUCTION

Infant gastroesophageal reflux disease (GERD) is a significant cause of concern to parents. This study seeks to describe GERD prevalence in infants, evaluate possible risk factors and assess common beliefs influencing management of GERD among Asian parents.

METHODS

Mother-infant dyads in the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO) cohort were prospectively followed from preconception to 12 months post-delivery. GERD diagnosis was ascertained through the revised Infant Gastroesophageal Reflux Questionnaire (I-GERQ-R) administered at 4 time points during infancy. Data on parental perceptions and lifestyle modifications were also collected.

RESULTS

The prevalence of infant GERD peaked at 26.5% at age 6 weeks, decreasing to 1.1% by 12 months. Infants exclusively breastfed at 3 weeks of life had reduced odds of GERD by 1 year (adjusted odds ratio 0.43, 95% confidence interval 0.19-0.97, P=0.04). Elimination of "cold or heaty food" and "gas producing" vegetables, massaging the infant's abdomen and application of medicated oil to the infant's abdomen were quoted as major lifestyle modifications in response to GERD symptoms.

CONCLUSION

Prevalence of GERD in infants is highest in the first 3 months of life, and the majority outgrow it by 1 year of age. Infants exclusively breastfed at 3 weeks had reduced odds of GERD. Cultural-based changes such as elimination of "heaty or cold" food influence parental perceptions in GERD, which are unique to the Asian population. Understanding the cultural basis for parental perceptions and health-seeking behaviours is crucial in tailoring patient education appropriately for optimal management of infant GERD.

Associations Between Maternal Distress During Early Life Periods and Offspring Respiratory Infections and Allergic Outcomes

Background

Increasing evidence suggests that maternal distress is a risk factor for development of respiratory infections and allergic diseases in the offspring. We aim to evaluate the link between maternal distress during critical periods in early life, namely the preconception, pregnancy and postnatal periods, and development of respiratory infections and allergic diseases in the offspring from the Singapore PREconception Study of long Term maternal and child Outcomes (S-PRESTO) cohort.

Methods

Maternal perceived distress was evaluated using validated questionnaires including Beck Depression Inventory-II (BDI-II) administered during three time periods: preconception (three months apart at four timepoints), pregnancy (during each trimester) and postnatal (3 and 6 months post-delivery). Child eczema, rhinitis and wheeze outcomes were evaluated using a modified ISAAC questionnaire at ages 3, 6, 12, and 18 months. Child allergic sensitization was determined by skin prick testing at 18 months.

Results

Among 332 mother-child pairs studied, higher maternal distress during preconception and pregnancy increased the risks of wheeze development in the first 18 months; for example, preconception and pregnancy BDI-II scores ≥20 were associated with increased risks of wheeze by 18 months [adjusted risk ratios 3.2 (95%CI 1.1-9.4) and 2.5 (1.0-5.9), respectively]. Emotional and practical support from family during preconception decreased the risks of offspring wheeze. No associations were observed between maternal distress and offspring eczema, rhinitis and allergic sensitization.

Conclusion

Maternal distress during critical early life periods was associated with offspring wheeze in the first 18 months of life. Supporting maternal mental health even before pregnancy could reduce the risk of offspring wheeze.

COVID-19-Related Life Experiences, Outdoor Play, and Long-term Adiposity Changes Among Preschool- and School-Aged Children in Singapore 1 Year After Lockdown

IMPORTANCE

Despite the potential for COVID-19 infection control-related events to have an effect on child well-being, comprehensive assessments of postlockdown changes and persistent outcomes are lacking.

OBJECTIVE

To survey the extent of COVID-19 lockdown-related lifestyle changes, their differences by child age and family socioeconomic status, and the potential association with child adiposity 1 year after lockdown.

DESIGN, SETTING, AND PARTICIPANTS

A self-administered, electronic survey was introduced to 2 ongoing child cohorts (the Singapore Preconception Study of Long-term Maternal and Child Outcomes [S-PRESTO] cohort of preschool children aged 1-4.5 years and the Growing Up in Singapore Towards Healthy Outcomes [GUSTO] cohort of primary school children aged 9-10.7 years) from July 8, 2020, to September 5, 2020, which was 1 to 3 months after the end of strict universal movement restrictions (duration of 73 days ending on June 19, 2020). All active participants from S-PRESTO and GUSTO, 2 population-based, longitudinal, parent-offspring cohorts in Singapore, were invited to participate and monitored through June 15, 2021.

EXPOSURES

Exposures included family income before and after the COVID-19 lockdown, changes in child outdoor play or exercise, and COVID-19-related life events; all data were self-reported by parents and school-aged children 1 to 3 months after the lockdown.

MAIN OUTCOMES AND MEASURES

Primary outcomes were self-reported COVID-19-related life events and changes in child online socialization, outdoor play or exercise, and intrafamily relationships. Study staff measured children's weight, height, and skinfold thickness before and up to 1 year after lockdown. Body mass indices (calculated as weight in kilograms divided by height in meters squared) and World Health Organization-standardized scores were computed. Differences before and after lockdown were compared using baseline-adjusted linear regression.

RESULTS

A total of 604 parents (53% of active cohort participants) and 356 school-aged children completed the survey and were similar to source cohorts. This represents 373 of 761 eligible children in the GUSTO cohort (mean [SD] age, 9.9 [0.4] years; 197 girls [52.8%]) and 231 of 370 eligible children in the S-PRESTO cohort (mean [SD] age, 2.6 [0.8] years; 121 boys [52.6%]). The COVID-19-related life changes were prevalent and varied (eg, 414 of 600 children [69.0%] reported changes in social activities). More than one-third of primary school-aged children (122 of 356 [34.3%]) and one-quarter of preschool-aged children (56 of 229 [24.5%]) eliminated any outdoor play after the lockdown. Lower family income before the lockdown was associated with increased odds of elimination of outdoor play (adjusted odds ratio per 1000 Singapore dollars [$730 US dollars] decrease, 1.09; 95% CI, 1.01-1.19). Complete elimination of outdoor activity (vs continued outdoor activity) was associated with an increase in body mass index of 0.48 (95% CI, 0.03-0.94) and a body mass index z score of 0.18 units (95% CI, 0-0.37) in school-aged children approximately 1 year after lockdown.

CONCLUSIONS AND RELEVANCE

Results of this cohort study suggest that 1 to 3 months after a brief, strict lockdown, a large proportion of parents and school-aged children reported elimination of outdoor play, which was more prevalent in lower-income families. Future research to better understand clinical implications and ways to mitigate lockdown outcomes is essential.

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.

Influence of red blood cell indices on HbA1c performance in detecting dysglycaemia in a Singapore preconception cohort study

Abnormalities of red blood cell (RBC) indices may affect glycated haemoglobin (HbA1c) levels. We assessed the influence of haemoglobin (Hb) and mean corpuscular volume (MCV) on the performance of HbA1c in detecting dysglycaemia among reproductive aged women planning to conceive. Women aged 18-45 years (n = 985) were classified as normal (12 ≤ Hb ≤ 16 g/dL and 80 ≤ MCV ≤ 100 fL) and abnormal (Hb < 12 g/dL and/or MCV < 80 fL). The Area Under the Receiver Operating Characteristic (AUROC) curve was used to determine the performance of HbA1c in detecting dysglycaemic status (prediabetes and diabetes). There were 771 (78.3%) women with normal RBC indices. The AUROCs for the normal and abnormal groups were 0.75 (95% confidence interval 0.69, 0.81) and 0.80 (0.70, 0.90), respectively, and were not statistically different from one another [difference 0.04 (- 0.16, 0.08)]. Further stratification by ethnicity showed no difference between the two groups among Chinese and Indian women. However, Malay women with normal RBC indices displayed lower AUROC compared to those with abnormal RBC indices (0.71 (0.55, 0.87) vs. 0.98 (0.93, 1.00), p = 0.002). The results suggest that the performance of HbA1c in detecting dysglycaemia was not influenced by abnormal RBC indices based on low Hb and/or low MCV. However, there may be ethnic variations among them.

Retinal microvasculature and time to pregnancy in a multi-ethnic pre-conception cohort in Singapore

STUDY QUESTION

Can abnormalities in retinal microvasculature representing adverse microcirculatory perfusion and inflammation shed light on the pathophysiology of female fecundability?

SUMMARY ANSWER

In our prospective study, abnormalities in retinal vascular geometric morphology (i.e. sparser arteriolar fractal and larger venular bifurcation) during pre-conception phase are temporarily associated with a prolonged time-to-pregnancy (TTP).

WHAT IS KNOWN ALREADY

Suboptimal retinal microcirculatory morphology has been associated with obesity, psychological stress and hypertension, all of which are known risk factors for reduced female fecundability.

STUDY DESIGN, SIZE, DURATION

A total of 652 women of Chinese, Malay or Indian ethnicity 18-45 years of age and planning to conceive spontaneously within the next 12 months were recruited during the pre-conception period into the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO), from February 2015 to October 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

During recruitment, we collected information on socio-demographic factors, menstrual characteristics and lifestyle behaviors and made anthropometric measurements. We assessed the following retinal microvascular features: caliber, branching angle and fractal dimension. We conducted follow-up telephone surveys to track each participant's pregnancy status at 6, 9 and 12 months after enrolment. We ascertained clinical pregnancies via ultrasonography, with TTP measured by the number of menstrual cycles required to achieve a clinical pregnancy over a 1-year follow-up. Then, we performed discrete-time proportional hazards models to estimate the fecundability odds ratio (FOR) and 95% CI for each retinal microvascular feature in association with TTP, after adjusting for major confounders, including body mass index and fasting glycemic level at study entry.

MAIN RESULTS AND THE ROLE OF THE CHANCE

Among 652 recruited women, 276 (42.3%) successfully conceived within 1 year of follow-up. The mean (and SD) was 1.24 (0.05) Df for retinal arteriolar dimension fraction and 78.45 (9.79) degrees for retinal venular branching angle, respectively. Non-linear relationship testing was performed before multiple adjustment in all associations and a non-monotonic association was detected between retinal venular branching angle and TTP. Compared with women in the highest tertile of retinal arteriolar fractal dimension, women in the second tertile had a prolonged TTP (FOR: 0.68; 95% CI: 0.51-0.92), as did women in the lowest tertile (FOR: 0.73; 95% CI: 0.55-0.98). Compared with women in the middle tertile of retinal venular branching angle, women in the highest tertile had a borderline prolonged TTP (FOR: 0.75; 95% CI: 0.56-1.02). No other retinal vascular features were significantly associated with TTP.

LIMITATIONS, REASONS FOR CAUTION

We were unable to adjust for other potential confounding factors such as female sexual function (e.g. frequency of sexual intercourse), which might introduce a residual bias. Moreover, even though this is a prospective cohort design, our findings can identify the temporal relationship but not necessarily infer a causal relationship between maternal microvasculature and TTP. Lastly, our study involving mainly Chinese, Malay and Indian ethnicities might not be generalizable to other races or ethnicities.

WIDER IMPLICATIONS OF THE FINDINGS

Suboptimal microcirculation may lead to reduced female fecundability. In the future, in addition to conventional ultrasonographic evaluation of ovarian and uterine physiological function, assessing the retinal microvasculature might be useful for assessment of ovarian age, fertility prediction and endometrial evaluation before assisted reproductive techniques for fertility treatments.

STUDY FUNDING/COMPETING INTEREST(S)

This research is supported by the Singapore National Research Foundation (NRF) under its Translational and Clinical Research (TCR) Flagship Programme and administered by the Singapore Ministry of Health's National Medical Research Council (NMRC) (Singapore-NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014) and Singapore National Medical Research Council Transition Award (NMRC TA/0027/2014). The authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT03531658.

Household environmental microbiota influences early-life eczema development

Exposure to a diverse microbial environment during pregnancy and early postnatal period is important in determining predisposition towards allergy. However, the effect of environmental microbiota exposure during preconception, pregnancy and postnatal life on development of allergy in the child has not been investigated so far. In the S-PRESTO (Singapore PREconception Study of long Term maternal and child Outcomes) cohort, we collected house dust during all three critical window periods and analysed microbial composition using 16S rRNA gene sequencing. At 6 and 18 months, the child was assessed for eczema by clinicians. In the eczema group, household environmental microbiota was characterized by presence of human-associated bacteria Actinomyces, Anaerococcus, Finegoldia, Micrococcus, Prevotella and Propionibacterium at all time points, suggesting their possible contributions to regulating host immunity and increasing the susceptibility to eczema. In the home environment of the control group, putative protective effect of an environmental microbe Planomicrobium (Planococcaceae family) was observed to be significantly higher than that in the eczema group. Network correlation analysis demonstrated inverse relationships between beneficial Planomicrobium and human-associated bacteria (Actinomyces, Anaerococcus, Finegoldia, Micrococcus, Prevotella and Propionibacterium). Exposure to natural environmental microbiota may be beneficial to modulate shed human-associated microbiota in an indoor environment.

Identification and reproducibility of dietary patterns assessed with a FFQ among women planning pregnancy

OBJECTIVE

To identify a posteriori dietary patterns among women planning pregnancy and assess the reproducibility of these patterns in a subsample using two dietary assessment methods.

DESIGN

A semi-quantitative FFQ was administered to women enrolled in the Singapore PREconception Study of long-Term maternal and child Outcomes study. Dietary patterns from the FFQ were identified using exploratory factor analysis (EFA). In a subsample of women (n 289), 3-d food diaries (3DFD) were also completed and analysed. Reproducibility of the identified patterns was assessed using confirmatory factor analysis (CFA) in the subsample, and goodness of fit of the CFA models was examined using several fit indices. Subsequently, EFA was conducted in the subsample and dietary patterns of the FFQ and the 3DFD were compared.

SETTING

Singapore.

PARTICIPANTS

1007 women planning pregnancy (18-45 years).

RESULTS

Three dietary patterns were identified from the FFQ: the 'Fish, Poultry/Meat and Noodles' pattern was characterised by higher intakes of fish, poultry/meat and noodles in soup; 'Fast Food and Sweetened Beverages' pattern was characterised by higher intakes of fast food, sweetened beverages and fried snacks; 'Bread, Legumes and Dairy' pattern was characterised by higher intakes of buns/ethnic breads, nuts/legumes and dairy products. The comparative fit indices from the CFA models were 0·79 and 0·34 for the FFQ and 3DFD of the subsample, respectively. In the subsample, three similar patterns were identified in the FFQ while only two for the 3DFD.

CONCLUSIONS

Dietary patterns from the FFQ are reproducible within this cohort, providing a basis for future investigations on diet and health outcomes.