KEY MESSAGES: A number of findings with a translational and clinical focus have already emerged. In the mothers, we found that changes and differences in food consumption varied across ethnic groups, with persistence of traditional beliefs, during pregnancy and the postpartum period. During pregnancy, higher maternal glucose levels, even in the absence of gestational diabetes mellitus, had graded relations with infant adiposity. Relations between maternal emotional health and birth outcomes and neurodevelopment have been identified. Genotype (25%) and in particular gene × environment interactions (75%) shape interindividual variations in the DNA methylome at birth. The complex effects of fixed genetic variations and different in utero environments can influence the epigenetic status at birth and the later-life phenotype.
CONCLUSIONS: The richness of the clinical data in 3 ethnicities, the extent of the biospecimen collection, and the extensive infancy and preschool follow-up have allowed us to study the biological pathways that link fetal development to health outcomes. In the coming years, more sophisticated analyses of epigenotype-phenotype relationships will become possible as the children grow and develop. Our studies will lead to the development of clinical and population-based interventions to reduce the burden of NCD.
METHODS: A cohort of 686 women (376 Chinese, 186 Malay, and 124 Indian) with a singleton pregnancy attended a clinic visit at 26-28 weeks of gestation as part of the Growing Up in Singapore Towards healthy Outcomes mother-offspring cohort study. Self-reported sleep quality and sleep duration were assessed using the Pittsburgh Sleep Quality Index (PSQI). GDM was diagnosed based on a 75-g oral glucose tolerance test administered after an overnight fast (1999 WHO criteria). Multiple logistic regression was used to model separately the associations of poor sleep quality (PSQI score > 5) and short nocturnal sleep duration (<6 h) with GDM, adjusting for age, ethnicity, maternal education, body mass index, previous history of GDM, and anxiety (State-Trait Anxiety Inventory score).
RESULTS: In the cohort 296 women (43.1%) had poor sleep quality and 77 women (11.2%) were categorized as short sleepers; 131 women (19.1%) were diagnosed with GDM. Poor sleep quality and short nocturnal sleep duration were independently associated with increased risk of GDM (poor sleep, adjusted odds ratio [OR] = 1.75, 95% confidence interval [CI] 1.11 to 2.76; short sleep, adjusted OR = 1.96, 95% CI 1.05 to 3.66).
CONCLUSIONS: During pregnancy, Asian women with poor sleep quality or short nocturnal sleep duration exhibited abnormal glucose regulation. Treating sleep problems and improving sleep behavior in pregnancy could potentially reduce the risk and burden of GDM.
METHODS: Participants were part of a prospective birth cohort study that recruited 1,247 pregnant women (57.2% Chinese, 25.5% Malay, and 17.3% Indian) during their first trimester. The 1,220 participants were followed up 3 weeks postpartum at home when questionnaires were administered to ascertain the frequency of adherence to the following confinement practices: showering; confinement-specific meals; going out with or without the baby; choice of caregiver assistance; and the use of massage therapy.
RESULTS: Most participants reported that they followed confinement practices during the first 3 weeks postpartum (Chinese: 96.4%, Malay: 92.4%, Indian: 85.6%). Chinese and Indian mothers tended to eat more special confinement diets than Malay mothers (p < 0.001), and Chinese mothers showered less and were more likely to depend on confinement nannies during this period than mothers from the two other ethnic groups (p < 0.001 for all). Malay mothers tended to make greater use of massage therapy (p < 0.001), whilst Indian mothers tended to have their mothers or mothers-in-law as assistant caregivers (p < 0.001).
CONCLUSION: Most Singapore mothers follow confinement practices, but the three Asian ethnic groups differed in specific confinement practices. Future studies should examine whether ethnic differences persist in later childrearing practices.
METHODS: 1136 pregnant women (56.7% Chinese, 25.5% Malay and 17.8% Indian) from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort study were screened for GDM by 75-g oral glucose tolerance test (OGTT) at 26-28 weeks of gestation. GDM was defined using the World Health Organization (WHO) criteria. High-risk screening is based on the guidelines of the UK National Institute for Health and Clinical Excellence.
RESULTS: Universal screening detected significantly more cases than high-risk screening [crude OR 2.2 (95% CI 1.7-2.8)], particularly for Chinese women [crude OR = 3.5 (95% CI 2.5-5.0)]. Pre-pregnancy BMI > 30 kg/m2 (adjusted OR = 3.4, 95% CI 1.5-7.9) and previous GDM history (adjusted OR = 6.6, 95% CI 1.2-37.3) were associated with increased risk of GDM in Malay women while GDM history was the only significant risk factor for GDM in Chinese women (adjusted OR = 4.7, 95% CI 2.0-11.0).
CONCLUSION: Risk factors used in high-risk screening do not sufficiently predict GDM risk and failed to detect half the GDM cases in Asian women. Asian women, particularly Chinese, should be screened to avoid under-diagnosis of GDM and thereby optimize maternal and fetal outcomes.
METHODS: Participants were 1,030 Singaporean women recruited during early pregnancy. Data collected included early breastfeeding experiences, breastfeeding duration, and mode of breastfeeding. Full breastfeeding was defined as the intake of breast milk, with or without water. Cox regression models were used to identify factors associated with discontinuation of any and full breastfeeding. Logistic regression analyses assessed the association of ethnicity with mode of breastfeeding.
RESULTS: At 6 months postpartum, the prevalence of any breastfeeding was 46 percent for Chinese mothers, 22 percent for Malay mothers, and 41 percent for Indian mothers; prevalence of full breastfeeding was 11, 2, and 5 percent, respectively. More Chinese mothers fed their infants expressed breast milk, instead of directly breastfeeding them, compared with the other two ethnic groups. Duration of any and full breastfeeding were positively associated with breastfeeding a few hours after birth, higher maternal age and education, and negatively associated with irregular breastfeeding frequency and being shown how to breastfeed. Adjusting for maternal education, breastfeeding duration was similar in the three ethnic groups, but ethnicity remained a significant predictor of mode of breastfeeding.
CONCLUSIONS: The low rates and duration of breastfeeding in this population may be improved with breastfeeding education and support, especially in mothers with lower education. Further work is needed to understand the cultural differences in mode of feeding and its implications for maternal and infant health.