The influence of dietary diversity on anthropometric status among young children ages 12 and 24 months in Wuhan, China.

The relative research on investigating the association between dietary diversity scores and anthropometric status among young children is few and inconsistent. Since understanding this association is quite essential to give more detailed advice about diet to ensure young children's healthy growth, we sought to determine the association between dietary diversity levels and anthropometric status among young children under 24 months. The study included 1408 mother-child pairs from the Tongji Maternal and Child Health Cohort, whose children range in age from 12 to 24 months. Multivariable logistic regressions were used to examine the effect of dietary diversity on children's anthropometric failure and obesity. All obese children aged 12 and 24 months had low-medium diverse diets in their first year of life. Risks of anthropometric failure for 12-month young children consumed low-medium diverse diets in their first year and 24-month young children consumed low-medium diverse diets in their second year are, respectively, 1.27 (odds ratio [OR], 95% confidence interval [CI] = [1.06-1.53]) and 1.19 (OR, 95% CI = [1.02-1.40]) times of those who consumed high diverse diets in corresponding year. The risk of anthropometric failure for 24-month-old children who consumed low-medium diverse diets during their first year of life is 4.70 (OR, 95% CI = [1.62-19.91]) times that of young children who consumed highly diverse diets during their first year of life. Introducing more diverse diets to young children under 24 months of age may be an effective strategy to prevent anthropometric failure and obesity in young children in later life.

Adverse associations between maternal deoxynivalenol exposure and birth outcomes: a prospective cohort study in China.

BACKGROUND: Deoxynivalenol (DON), one of the most prevalent mycotoxins, has been found to cause fetal growth retardation in animals. However, limited evidence exists regarding its effects on pregnant women. METHODS: Maternal urinary concentration of total DON (tDON) and free DON (fDON) in the second trimester was measured using liquid chromatography with tandem mass spectrometry. Provisional daily intake (PDI) of DON was calculated based on tDON concentration. Linear and logistic regression models were used to evaluate the association between DON exposure levels and birth weight, birth length, and the risk of small for gestational age (SGA). RESULTS: Among 1538 subjects, the median concentrations of tDON and fDON were 12.1 ng/mL and 5.1 ng/mL, respectively. The PDI values revealed that the median DON intake was 0.7 µg/kg bw, and 35.9% of the total population exceeded the provisional maximum tolerable daily intake (PMTDI) of 1 µg/kg bw. Compared with the lowest tertile, birth weight decreased by 81.11 g (95% CI: -127.00, -35.23) for tDON (P-trend < 0.001) and 63.02 g (95% CI: -108.72, -17.32) for fDON (P-trend = 0.004) in the highest tertile. Each unit increase in Ln-tDON and Ln-fDON was also inversely associated with birth weight. Furthermore, compared to those who did not exceed PMTDI, pregnant women whose PDI exceeded PMTDI had lower birth weight (ß = -79.79 g; 95% CI: -119.09, -40.49) and birth length (ß = -0.21 cm; 95% CI: -0.34, -0.07), and a higher risk of SGA (OR = 1.48; 95% CI: 1.02, 2.15) in their offspring. Similar associations with birth weight, birth length, and SGA were found when comparing the highest tertile of PDI to the lowest tertile (all P-trend < 0.05). CONCLUSIONS: Maternal DON exposure is related to decreased birth weight. Our findings implicate that DON exposure during pregnancy may cause fetal growth faltering, and measures should be taken to reduce DON exposure in pregnant women.

Association of elevated mid-pregnancy maternal plasma ferritin concentrations and triglyceride concentrations with the risk of gestational diabetes mellitus: A prospective cohort study.

OBJECTIVE: Ferritin levels are well known to be associated with gestational diabetes mellitus (GDM). However, the association of the combination of ferritin and triglyceride (TG) levels in early mid-pregnancy with GDM has not been studied in depth. We investigated the independent and combined relationships of plasma ferritin and TG concentrations with the risk of GDM as well as the mediation effect of TG on ferritin. METHODS: We analysed 2071 pregnant women from the Tongji Maternal and Child Health Cohort who had their plasma ferritin and TG concentrations measured at 11-20 weeks of gestation. Associations between ferritin and TG concentrations and GDM risk were estimated using multivariable logistic regression models. Youden's index was calculated to find the cut-off values of ferritin and TG by ROC curve analysis. The mediation effect of the TG concentration on the ferritin level with GDM risk was explored by a mediation analysis. RESULTS: A total of 264 (12.3%) participants developed GDM. The median and IQR of ferritin was 53.9 (30.5-92.7) ng/mL. After adjusting for potential confounders, the relative risks (RRs) and 95% confidence intervals of GDM were 2.19 (1.42, 3.39) for ferritin and 2.02 (1.37, 2.97) for TG. The adjusted RR for combination was 2.40 (1.62, 3.55). Moreover, we found that the TG concentration mediated 15.0% of the total effect of the ferritin concentration on the risk of GDM. CONCLUSIONS: Women with a combination of both high plasma ferritin (˃55.7 ng/mL) and high TG (˃1.9 mmoL/L) were at the highest risk of GDM. Additionally, we have revealed for the first time that an elevated maternal TG concentration in early pregnancy mediates the relationship between ferritin concentration and GDM risk. TRIAL REGISTRATION: This trial is registered at https://ClinicalTrials.gov as NCT03099837.

Association of Breastfeeding Practices During the First 3 Months with Infant Sleep Trajectories: A Prospective Cohort Study.

BACKGROUND: Breastfeeding has numerous effects on maternal and child health. The effect of breastfeeding on infant sleep remains inconclusive. OBJECTIVES: We aimed to examine whether full breastfeeding (FBF) during the first 3 mo is associated with longitudinal infant sleep trajectories in their first 2 y of life. METHODS: The study was embedded in the Tongji Maternal and Child Health Cohort study. Information on infant feeding practices was collected at 3 mo of age, and maternal/child pairs were assigned to the FBF or the non-FBF group (including partially breastfeeding and exclusive formula feeding) on the basis of feeding practices during the first 3 mo of life. Sleep data of infants were obtained at 3, 6, 12, and 24 mo. Total, night, and day sleep trajectories across 3 to 24 mo were estimated with group-based models. Each sleep trajectory was differentiated on the basis of sleep duration at 3 mo (long/moderate/short) and the interval from 6 to 24 mo (moderate/short). Multinomial logistic regression was used to investigate the association of breastfeeding practices with infant sleep trajectories. RESULTS: Among the 4056 infants studied, 2558 (63.1%) received FBF for 3 mo. When compared with FBF infants, non-FBF infants had shorter sleep duration at 3, 6, and 12 mo (P < 0.01). Non-FBF infants were more likely to experience Moderate-Short (OR: 1.31; 95% CI: 1.06, 1.61) and Short-Short (OR: 1.56; 95% CI: 1.12, 2.16) total sleep trajectories and more likely to experience Moderate-Short (OR: 1.84; 95% CI: 1.22, 2.77), and Short-Moderate (OR: 1.40; 95% CI: 1.06, 1.85) night sleep trajectories than FBF infants. CONCLUSIONS: Full breastfeeding for ≥3 mo were positively associated with longer infant sleep duration. Infants fully breastfed were more likely to experience better sleep trajectories characterized by longer duration in their first 2 y of life. Full breastfeeding may benefit infants through healthy sleep.

Vitamin D supplementation and lower respiratory tract infection in infants: a nested case-control study.

PURPOSE: To assess the association between vitamin D (VD) supplementation and the risk of lower respiratory tract infection (LRTI) among infants. METHODS: This is a nested case-control study from an ongoing prospective birth cohort in Wuhan from 2013. Cases were subjects free of neonatal pneumonia but later developed LRTI during infancy, who were matched with five randomly selected controls by infant sex, birth year, and birth season. We included 190 cases and 950 controls in the final analysis. The primary outcome was the first LRTI incident and the exposure was VD supplementation from birth to the index endpoint. The association between VD supplementation and LRTI risk was assessed using the Cox proportional-hazards regression model. RESULTS: Infants taking supplements had a 59% relative reduction in the hazard ratio of LRTI (HR = 0.41; 95% CI 0.26, 0.64) compared to those not supplemented. There was a linear relationship between LRTI risk and VD supplementation within range of 0-603 IU/day: for each 100 IU per day increment in VD supplementation, infants experienced a 21% lower risk of developing LRTI (adjusted HR: 0.79; 95% CI 0.71, 0.89). The linear relationship was stably observed in the sensitivity analyses as well. CONCLUSIONS: VD supplementation was associated with the reduced risk of LRTI throughout infancy, and the optimal supplementation dose for infants may be beyond the current recommendation.

Patterns of maternal gestational weight gain in association with allergic diseases in offspring: A prospective cohort study.

OBJECTIVE: To evaluate the association between patterns of gestational weight gain (GWG) and allergic diseases in offspring. DESIGN: Prospective cohort study. SETTING: Prenatal clinics in Wuhan, China. POPULATION: A cohort of 2546 mother and offspring pairs were enrolled before 16 weeks of gestation and followed up to 24 months postpartum. METHODS: Maternal body weights were measured regularly during pregnancy, and their GWG patterns were estimated using the growth mixture model. Robust Poisson models were used to evaluate relative risk (RR) and 95% CI after multivariable adjustment. MAIN OUTCOME MEASURES: Offspring atopic allergy and allergic contact dermatitis were defined according to a physician's diagnosis reported by the mother, and food allergy was reported by the mother. RESULTS: Three GWG patterns were identified: 18.1% (461) of the women were described as pattern 1, characterised by rapid GWG earlier in pregnancy; 56.6% (1442) of the women were described as pattern 2, with steady GWG throughout pregnancy; and 25.3% (643) of the women was described as pattern 3, with rapid GWG later in pregnancy. By the age of 24 months, 360 (14.1%), 109 (4.3%) and 757 (29.7%) offspring had atopic allergy, allergic contact dermatitis or food allergy, respectively. Compared with women in GWG pattern 2, the RRs (95% CIs) among women in pattern 1 were 0.74 (0.55-0.99) for atopic allergy, 0.64 (0.36-1.15) for allergic contact dermatitis and 0.95 (0.81-1.12) for food allergy. CONCLUSIONS: Maternal GWG pattern characterised by rapid GWG earlier in pregnancy was associated with a lower risk of atopic allergy in offspring.

Increased food diversity in the first year of life is inversely associated with allergic outcomes in the second year.

BACKGROUND: The evidence on the relationship between diet diversity in early life and allergic outcomes was few and inconsistent. We sought to determine the association of food diversity in the first year of life with allergic outcomes in the second year. METHODS: Two thousand two hundred fifty-one mother-infant pairs from Tongji Maternal and Child Health Cohort (TMCHC) were involved in the study. Information on complementary foods introduction was obtained by telephone interview at 6- and 12-month postpartum follow-up. Any doctor-diagnosed allergic diseases in the second year were recorded at 2-year postpartum follow-up. Food allergies in infancy were assessed and self-reported by mothers at each postpartum follow-up. Multivariable logistic regression was used to examine the effect of food diversity at 6 and 12 months of age on later allergic diseases and food allergy. RESULTS: A total of 135 (6.0%) infants reported allergic diseases at between 1 and 2 years of age. Independent of food allergy history of infants and other potential confounders, less food diversity at 6 months of age was associated with increased risk of later allergic diseases (OR 2.17, 95% CI 1.04-4.50 for 0 vs. 3-6 food groups). By 12 months of age, significant inverse associations with later allergic diseases (OR 2.35, 95% CI 1.03-5.32 for 1-5 vs. 8-11 food groups, and OR 1.98, 95% CI 1.16-3.37 for 6-7 vs. 8-11 food groups) and food allergy (OR 2.10, 95% CI 1.29-3.42 for 1-5 vs. 8-11 food groups) were observed. Children with higher food diversity in both periods had the lowest risk of allergic diseases during the second year of life. CONCLUSIONS: A more diverse diet within the first year of life was associated with reduced risk of allergic diseases at 1-2 years of age. Introducing higher diversity of foods from 6 to 12 months of age might be an effective strategy to improve the allergy outcomes of infants in later life.

Association of maternal low-carbohydrate-diet score during pregnancy with allergic diseases at 2 years of age.

BACKGROUND: We prospectively evaluated the association between low-carbohydrate-diet (LCD) score during pregnancy and the risk of allergic diseases in infants up to 2 years. METHODS: Participants were from a prospective mother-offspring cohort study in Wuhan, China. LCD score was calculated according to the percentage of dietary energy intake from carbohydrate, protein, and fat assessed in late pregnancy using validated food frequency questionnaires. Allergic diseases, including immunoglobulin E (IgE)-mediated allergic diseases, allergic contact dermatitis, and food allergy, were recorded at 3, 6, 12, and 24 months postpartum follow-up. Poisson regression models were used to calculate relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: Among 1636 mother-infant pairs included in the present analysis, 230 infants (14.1%) with IgE-mediated allergic diseases, 77 (4.7%) with allergic contact dermatitis, and 488 (29.8%) with food allergy were, respectively, reported. Independent of total energy intake and other potential confounders, both the lowest quintile (RR, 1.77; 95% CI, 1.13-2.77) and the highest quintile (RR, 1.72; 95% CI, 1.22-2.63), were associated with the risk of IgE-mediated allergic diseases compared with the middle quintile. Among high-carbohydrate-diet pregnant women, substituting 5% of energy from either protein or fat for carbohydrate was associated with a lower risk of IgE-mediated allergic diseases. While among low-carbohydrate-diet pregnant women, substituting 5% of energy from carbohydrate, especially high-quality carbohydrate, for fat was associated with a lower risk of IgE-mediated allergic diseases. CONCLUSION: Maternal low carbohydrate-high protein and fat, and high carbohydrate-low protein and fat diet were both associated with an increased risk of allergic diseases in the infants up to 2 years. This study may provide an intervention strategy for allergy prevention in early childhood.

Timing of gestational weight gain in association with birth weight outcomes: a prospective cohort study.

Maternal gestational weight gain (GWG) is an important determinant of infant birth weight, and having adequate total GWG has been widely recommended. However, the association of timing of GWG with birth weight remains controversial. We aimed to evaluate this association, especially among women with adequate total GWG. In a prospective cohort study, pregnant women's weight was routinely measured during pregnancy, and their GWG was calculated for the ten intervals: the first 13, 14-18, 19-23, 24-28, 29-30, 31-32, 33-34, 35-36, 37-38 and 39-40 weeks. Birth weight was measured, and small-for-gestational-age (SGA) and large-for-gestational-age were assessed. Generalized linear and Poisson models were used to evaluate the associations of GWG with birth weight and its outcomes after multivariate adjustment, respectively. Of the 5049 women, increased GWG in the first 30 weeks was associated with increased birth weight for male infants, and increased GWG in the first 28 weeks was associated with increased birth weight for females. Among 1713 women with adequate total GWG, increased GWG percent between 14 and 23 weeks was associated with increased birth weight. Moreover, inadequate GWG between 14 and 23 weeks, compared with the adequate GWG, was associated with an increased risk of SGA (43 (13·7 %) v. 42 (7·2 %); relative risk 1·83, 95 % CI 1·21, 2·76). Timing of GWG may influence infant birth weight differentially, and women with inadequate GWG between 14 and 23 weeks may be at higher risk of delivering SGA infants, despite having adequate total GWG.

Plasma Manganese Levels and Risk of Gestational Diabetes Mellitus: A Prospective Cohort Study.

Manganese (Mn) intake has been found to be linked with risk of type 2 diabetes. However, the role of Mn in the development of gestational diabetes mellitus (GDM) remains to be investigated. This prospective study included pregnant women from the Tongji Maternal and Child Health Cohort. A total of 2327 participants with plasma specimens before 20 weeks were included. Among the pregnant women, 9.7% (225/2327) were diagnosed with GDM. After adjustment, pregnant women with the third and highest quartile of plasma Mn levels had 1.31-fold (RR, 2.31 [1.48, 3.61]) and 2.35-fold (RR, 3.35 [2.17, 5.17]) increased risk of GDM compared with those with the lowest quartile. A 1 standard deviation increment of ln-transformed plasma Mn levels (0.53 µg/L) was related to elevated risks of GDM with RRs of 1.28 [1.17, 1.40]. The positive associations between Mn and GDM remained consistent in all the subgroups. The weighted quantile sum index was significantly related to GDM (RR, 1.60 [1.37, 1.86]). The contribution of Mn (58.69%) to the metal mixture index was the highest related to GDM. Higher plasma Mn levels were found to be linked with elevated fasting and 2 h post-load blood glucose. This study revealed relationships of higher plasma Mn levels in early pregnancy and increased risk of GDM, suggesting that though essential, excess Mn in the body might be a potential important risk factor for GDM.

The association of maternal vaginal bleeding and progesterone supplementation in early pregnancy with offspring outcomes: a prospective cohort study.

BACKGROUND: Progesterone is widely used to improve the adverse pregnancy outcomes related to vaginal bleeding during early pregnancy. However, the evidence of its effectiveness is equivocal. METHODS: Six thousand six hundred fifteen mother-infant pairs from Tongji Maternal and Child Health Cohort (TMCHC) were involved in the study. Information on vaginal bleeding, progesterone administration in early pregnancy were obtained at enrolment. Birth outcomes were obtained from the hospital notes. Body weight of the infants at 12 months of age was collected by telephone interview. Multivariable logistic regression was conducted to estimate the effect of vaginal bleeding and progesterone administration in early pregnancy on birth outcomes and weight status of infants at 12 months of age. RESULTS: 21.4% (1418/6615) participants experienced bleeding in early pregnancy, and 47.5% (674/1418) of them were treated with progesterone. There were no significant associations between progesterone supplementation in early pregnancy and offspring outcomes. Compared to women without bleeding or any therapy, women with bleeding and progesterone therapy experienced increased risk of preterm (OR 1.74, 95% CI 1.21-2.52), and delivering a small-for-gestational-age (SGA) (OR 1.46, 95% CI 1.07-1.98) or low birth weight (LBW) (OR 2.10, 95% CI 1.25-3.51) neonate, and offspring of them had an increased risk of weight for age z-score (WAZ) < -1 at 12 months of age (OR 1.79, 95%CI 1.01-3.19). CONCLUSIONS: Offspring of mothers with bleeding and progesterone therapy were more likely to be a premature, SGA or LBW neonate, and had lower weight at 12 months of age. Progesterone supplementation may have no beneficial effect on improving adverse offspring outcomes related to early vaginal bleeding. TRIAL REGISTRATION: TMCHC was registered at clinicaltrials.gov as NCT03099837 on 4 April 2017.

The overall plant-based diet index during pregnancy and risk of gestational diabetes mellitus: a prospective cohort study in China.

The high overall plant-based diet index (PDI) is considered to protect against type 2 diabetes in the general population. However, whether the PDI affects gestational diabetes mellitus (GDM) risk among pregnant women is still unclear. We evaluated the association between PDI and GDM risk based on a Chinese large prospective cohort - the Tongji Maternal and Child Health Cohort. Dietary data were collected at 13-28 weeks of pregnancy by a validated semi-quantitative FFQ. The PDI was obtained by assigning plant food groups positive scores while assigning animal food groups reverse scores. GDM was diagnosed by a 75 g 2-h oral glucose tolerance test at 24-28 weeks of gestation. Logistic regression models were fitted to estimate OR of GDM, with associated 95 % CI, comparing women in different PDI quartiles. Among the total 2099 participants, 169 (8·1 %) were diagnosed with GDM. The PDI ranged from 21·0 to 52·0 with a median of 36·0 (interquartile range (IQR) 33·0-39·0). After adjusting for social-demographic characteristics and lifestyle factors etc., the participants with the highest quartile of PDI were associated with 57 % reduced odds of GDM compared with women in the lowest quartile of PDI (adjusted OR 0·43; 95 % CI 0·24, 0·77; Pfor trend = 0·005). An IQR increment in PDI was associated with 29 % decreased odds of GDM (adjusted OR 0·71; 95 % CI 0·56, 0·90). Findings suggest that adopting a plant-based diet during pregnancy could reduce GDM risk among Chinese women, which may be valuable for dietary counselling during pregnancy.

Exposure to environmental tobacco smoke during pregnancy and infancy increased the risk of upper respiratory tract infections in infants: A birth cohort study in Wuhan, China.

We aimed to evaluate the association of the exposure to environmental tobacco smoke (ETS) during pregnancy and infancy with the risk of upper respiratory tract infections (URTI) in infants based on a Chinese birth cohort study. Among 4178 infants who constituted the final study population, 46.8% experienced URTI in their first year of life. The hazard ratios (HR) and 95% confidence intervals (CI) for the risk of URTI were assessed using Cox regression models. Compared with no ETS during pregnancy, continued ETS during pregnancy was independently associated with a higher risk of URTI (HR: 1.36, 95% CI: 1.13, 1.63) after adjustment for potential confounders and also associated with earlier occurrence of URTI (log-rank P = .002). The association remained consistent across the strata defined according to maternal age, number of siblings, sex, and breastfeeding. Exposure to ETS during infancy was associated with URTI only among infants who were breastfed for less than 12 months (P for interaction < 0.05).Furthermore, infants exposed to ETS during both pregnancy and infancy showed the highest HR of 1.46 (95% CI: 1.16, 1.85) for URTI. Efforts should be made to protect pregnant women and infants from the adverse effects of indoor and outdoor ETS.

Optimal gestational weight gain in Chinese pregnant women by Chinese-specific BMI categories: a multicentre prospective cohort study.

OBJECTIVE: To establish optimal gestational weight gain (GWG) in Chinese pregnant women by Chinese-specific BMI categories and compare the new recommendations with the Institute of Medicine (IOM) 2009 guidelines. DESIGN: Multicentre, prospective cohort study. Unconditional logistic regression analysis was used to evaluate the OR, 95 % CI and the predicted probabilities of adverse pregnancy outcomes. The optimal GWG range was defined as the range that did not exceed a 1 % increase from the lowest predicted probability in each pre-pregnancy BMI group. SETTING: From nine cities in mainland China. PARTICIPANTS: A total of 3731 women with singleton pregnancy were recruited from April 2013 to December 2014. RESULTS: The optimal GWG (ranges) by Chinese-specific BMI was 15·0 (12·8-17·1), 14·2 (12·1-16·4) and 12·6 (10·4-14·9) kg for underweight, normal weight and overweight pregnant women, respectively. Inappropriate GWG was associated with several adverse pregnancy outcomes. Compared with women gaining weight within our proposed recommendations, women with excessive GWG had higher risk for macrosomia, large for gestational age and caesarean section, whereas those with inadequate GWG had higher risk for low birth weight, small for gestational age and preterm delivery. The comparison between our proposed recommendations and IOM 2009 guidelines showed that our recommendations were comparable with the IOM 2009 guidelines and could well predict the risk of several adverse pregnancy outcomes. CONCLUSIONS: Inappropriate GWG was associated with higher risk of several adverse pregnancy outcomes. Optimal GWG recommendations proposed in the present study could be applied to Chinese pregnant women.

Association between the maternal protein nutrition status during pregnancy and the risk of preterm birth.

We aimed to assess protein nutrition status during pregnancy by maternal plasma total protein (MTP) levels in urban pregnant women and to explore the association between the trimester-specific MTP levels and risk of preterm birth (PTB). A prospective design was conducted in 3,382 mother-newborn pairs with the second-trimester maternal MTP information and in 3,478 mother-newborn pairs with the third-trimester MTP information. Multiple Cox proportional hazard regression and multiple linear regression were used to analyse the associations between MTP levels and PTB risk as well as gestational duration, respectively. Nearly all the second-trimester MTP levels were within the clinical reference range, but more than 40% of the third-trimester MTP levels were less than the lower limit of normal. No significant association was found between the second-trimester MTP level and PTB risk. However, the adjusted hazard ratios (HRs) of PTB across increasing quartiles of the third-trimester MTP levels were 1.00 (reference), 0.59 (0.36, 0.95), 0.35 (0.20, 0.60), and 0.32 (0.19, 0.53) (p for trend < 0.001), respectively. Each standard deviations increment of the third-trimester MTP was associated with increase of 0.13 weeks in gestational duration. Moreover, stratified analyses showed that the effects of third-trimester MTP on PTB risk and gestational duration were stronger in pregnant women carrying female offspring than those carrying male offspring (p for interaction < 0.05). The third-trimester MTP level was inversely associated with PTB risk and was positively associated with gestational duration. Improving third-trimester MTP level may be helpful for preventing PTB.

The Associations of Ambient Fine Particulate Matter Exposure During Pregnancy With Blood Glucose Levels and Gestational Diabetes Mellitus Risk: A Prospective Cohort Study in Wuhan, China.

Investigators in previous studies have drawn inconsistent conclusions regarding the relationship between relatively low exposure to fine particulate matter (particulate matter with an aerodynamic diameter ≤2.5 µm (PM2.5)) and risk of gestational diabetes mellitus (GDM), while the association between high PM2.5 exposure and GDM risk has not been well studied. We investigated the association of high PM2.5 exposure during pregnancy with blood glucose levels and GDM risk in Chinese women. The present study was conducted from August 2013 to May 2016 among 3,967 pregnant women in the Tongji Maternal and Child Health Cohort in Wuhan, China. PM2.5 exposure during pregnancy for each participant was estimated by means of land-use regression models. An interquartile-range increase in PM2.5 exposure (33.84 µg/m3 for trimester 1 and 33.23 µg/m3 for trimester 2) was associated with 36% (95% confidence interval (CI): 1.15, 1.61) and 23% (95% CI: 1.01, 1.50) increased odds of GDM during trimester 1 and trimester 2, respectively. An interquartile-range increment of PM2.5 exposure during trimester 1 increased 1-hour and 2-hour blood glucose levels by 1.40% (95% CI: 0.42, 2.37) and 1.82% (95% CI: 0.98, 2.66), respectively. The same increment of PM2.5 exposure during trimester 2 increased fasting glucose level by 0.85% (95% CI: 0.41, 1.29). Our findings suggest that high PM2.5 exposure during pregnancy increases blood glucose levels and GDM risk in Chinese women.

Delayed Lactogenesis Is Associated with Suboptimal Breastfeeding Practices: A Prospective Cohort Study.

BACKGROUND: Breastfeeding has many established health benefits to both babies and mothers. There is limited evidence on the association between delayed lactogenesis and breastfeeding practices. OBJECTIVE: We assessed the association between delayed lactogenesis and breastfeeding practices in women initiating breastfeeding. DESIGN: We used data from a prospective cohort study in Wuhan, China, which enrolled pregnant women at 8-16 weeks of gestation and followed up to postpartum. Women were included who had a singleton live birth, initiated breastfeeding, and provided information on infant feeding. Maternal lactogenesis status was assessed by face-to-face interview at day 4 postpartum. Breastfeeding practices (full breastfeeding and/or any breastfeeding) were queried by telephone interview at 3, 6, and 12 mo postpartum. Poisson regression and Cox regression were used to identify the association between delayed lactogenesis and breastfeeding practices. RESULTS: Delayed lactogenesis was reported by 17.9% of the 2877 participants. After adjusting for potential confounders, when compared with timely lactogenesis, delayed lactogenesis was significantly associated with higher risk of inability to sustain full breastfeeding at 3 mo postpartum (RR: 1.24, 95% CI: 1.10, 1.39) and 6 mo postpartum (RR: 1.14, 95% CI: 1.04, 1.24). Delayed lactogenesis was also significantly associated with early termination of any breastfeeding (HR: 1.15, 95% CI: 1.01, 1.30) in the adjusted model. In a combined analysis, women with higher gestational weight gain (GWG, ≥16 kg for underweight and normal weight, 15 kg for overweight/obesity) and who subsequently experienced delayed lactogenesis had the highest risk of ending any breastfeeding earlier (adjusted HR: 1.32, 95% CI: 1.11, 1.55) compared with those who gained less GWG and experienced timely lactogenesis. CONCLUSIONS: This study shows that delayed lactogenesis was associated with low rate of full breastfeeding and shorter duration of any breastfeeding. Greater efforts to promote breastfeeding should be targeted towards women with delayed lactogenesis.

Association of vitamin D supplementation with respiratory tract infection in infants.

Vitamin D deficiency has been reported to be associated with respiratory tract infection (RTI). However, evidence regarding the effects of vitamin D supplementation on susceptibility of infants to RTI is limited. In this prospective birth cohort study, we examined whether vitamin D supplementation reduced RTI risk in 2,244 infants completing the follow-up from birth to 6 months of age. The outcome endpoint was the first episode of paediatrician-diagnosed RTI or 6 months of age when no RTI event occurred. Infants receiving vitamin D supplements at a daily dose of 400-600 IU from birth to the outcome endpoint were defined as vitamin D supplementation and divided into four groups according to the average frequency of supplementation: 0, 1-2, 3-4, and 5-7 days/week. We evaluated the relationship between vitamin D supplementation and time to the first episode of RTI with Kaplan-Meier plots. The associations of vitamin D supplementation with infant RTI, lower RTI (LRTI), and RTI-related hospitalization were assessed using modified Poisson regression. The median time to first RTI episode was 60 days after birth (95% CI [60, 90]) for infants without supplementation and longer than 6 months of age for infants with supplementation (p < .001). We observed inverse trends between supplementation frequency and risk of RTI, LRTI, and RTI-related hospitalization (p for trend < .001), with the risk ratios in the 5-7 days/week supplementation group of 0.46 (95% CI [0.41, 0.50]), 0.17 (95% CI [0.13, 0.24]), and 0.18 (95% CI [0.12, 0.27]), respectively. These associations were significant and consistent in a subgroup analysis stratified by infant feeding.

The association between intake of dietary lycopene and other carotenoids and gestational diabetes mellitus risk during mid-trimester: a cross-sectional study.

This study aimed to determine whether increased carotenoids intake was associated with reduced risk of gestational diabetes mellitus (GDM). We performed a cross-sectional analysis using data from Tongji Maternal and Child Health Cohort study. The dietary carotenoids intake of 1978 pregnant women was assessed using a researcher-administered FFQ before undertaking an oral glucose tolerance test at 24-28 weeks. Multivariate logistic and linear regression analyses were used to obtain the effect estimates. Participants in the highest quartile of lycopene intake showed a lower risk of GDM (OR 0·50; 95 % CI 0·29, 0·86; P for trend = 0·007) compared with those in the lowest quartile; each 1 mg increase in lycopene consumption was associated with a 5 % (95 % CI 0·91, 0·99; P for trend = 0·020) decrease in GDM risk. No significant association was found between α-carotene, ß-carotene, ß-cryptoxanthin, lutein/zeaxanthin intake and GDM risk. Multiple linear regression analysis suggested an inverse association between lycopene intake and fasting blood glucose (FBG) (P for trend < 0·001); each 1 mg increase in lycopene intake was associated with 0·005 (95 % CI 0·002, 0·007; P for trend < 0·001) mmol/l decrease in FBG. Interaction analysis indicated consistent effect on each age or pre-BMI subgroup; however, a stronger protective effect of lycopene intake against GDM was observed among primigravid women (OR 0·20; 95 % CI 0·07, 0·55 in the highest v. the lowest quartile of intake; P for interaction = 0·036). In conclusion, dietary lycopene intake was mainly assumed via reducing FBG to decrease GDM risk, and the protection was relatively increased among primigravid women.

[Optimal gestational weight gain for Chinese urban women].

OBJECTIVE: To examine optimal gestational weight gain(GWG) for Chinese pregnant women. METHODS: A total of 6998 women with singleton and term pregnancy recruited to the Tongji Maternal and Child Health Cohort during January 2013 to May 2016 in Wuhan, Hubei were included. Information on sociodemographic, medical and family history of disease was obtained by questionnaire, body weight and height were measured at the first antenatal care during 8-16 weeks of gestation. Prenatal weight of mothers were measured, and gestational week, mode of delivery, pregnancy complications, gender of newborn, birth weight and length were collected from medical records after delivery. Restricted cubic spline was used to model nonlinear relationships between GWG and the occurrence of small for gestational age(SGA), large for gestational age(LGA), low birth weight(LBW), macrosomia, cesarean, gestational hypertension(GH)and gestational diabetes mellitus(GDM), respectively. The GWG of the lowest risks for adverse pregnant outcomes was regarded as optimal GWG recommended by Tongji(TJ) for pregnant women. The P25-P75 of GWG was defined as the optimal GWG recommended by percentile method. Logistic regression was used to analyze the effect of excessive or insufficient GWG on adverse pregnancy outcomes, while the recommendations of TJ and percentile method were used as references, respectively. RESULTS: (1) The GWG with lower risk of adverse pregnant outcomes based on pre-gravid body mass index(BMI) are 12. 0-17. 0 kg for underweight, 9. 0-14. 0 kg for normal weight and 7. 0-11. 0 kg for overweight, respectively, which are defined as TJ recommendations. The recommended GWG by percentile method are 14. 0-19. 0 kg for underweight, 13. 0-19. 0 kg for normal weight, 10. 8-18. 0 kg for overweight and 9. 0-15. 8 kg for obesity, respectively. (2) Compared to women gain within the TJ recommendations, OR of LGA is 2. 94(95%CI 2. 31-3. 73), macrosomia is 3. 13(95%CI 2. 38-4. 13), cesarean is 1. 53(95%CI 1. 38-1. 71) and GH is 2. 18(95%CI 1. 50-3. 17) for those with excessive GWG, OR of SGA is 1. 82(95%CI 1. 32-2. 53) for those who gain less. The corresponding ORs according to percentile method are 2. 11(95%CI 1. 76-2. 54) for LGA, 2. 16(95%CI 1. 76-2. 65) for macrosomia, 1. 53(95%CI 1. 36-1. 72) for cesarean, 1. 39(95%CI 1. 02-1. 90) for GH and 1. 60(95%CI 1. 29-1. 99) for SGA, respectively. CONCLUSION: The optimal GWG of Chinese pregnant women recommended by the study are 12. 0-17. 0 kg for pre-gravid underweight women, 9. 0-14. 0 kg for normal weight women and 7. 0-11. 0 kg for overweight, respectively.