Ethnic differences in term birthweight: the role of constitutional and environmental factors

Comparison of singleton and twin birth weight reference percentile curves by gestational age and sex in extremely preterm infants: a population-based study

BACKGROUND

With the increasing survival rate of smaller newborns and twins, previous growth curves may not accurately assess the growth of extremely preterm infants (EPIs). Our study aimed to establish birth weight percentile curves for singletons and twins in EPIs from China and the USA and compare the differences between them.

METHODS

In China, EPIs were from 31 provinces, from 2010 to 2021. The collected information was sex, gestational age, birth weight, singletons and twins. We used the generalised additive models for location scale and shape method to construct the birth weight percentile curves by gestational age and sex for EPIs. The National Vital Statistics System database from 2016 to 2021 was also analysed. We compared the differences between the 50th birth weight percentile curves of the two databases.

RESULTS

We identified 8768 neonates in China (5536 singletons and 3232 twins) and 121 933 neonates in the USA (97 329 singletons and 24 604 twins). We established the 3rd, 10th, 25th, 50th, 75th, 90th and 97th birth weight reference curves for China and the USA. The results showed that males had higher birth weights than females. In China, for the same gestational age and sex, birth weights in singletons and twins were found to be similar, though singleton males born in China had slightly higher birth weights than male twins. In the USA, birth weights were also similar for females and males, with the same gestational age in singletons and twins.

CONCLUSION

We established birth weight reference percentile curves by gestational age and sex for singletons and twins among EPIs in China and the USA.

Determinants of dysmenorrhoea among female adolescents: results from a community-based cohort study in Amsterdam

RESEARCH QUESTION

What is the contribution of sociodemographic, psychosocial, lifestyle and reproductive factors up to the age of 11-12 years to the occurrence of dysmenorrhoea at age 15-16 years within the Amsterdam Born Children and their Development (ABCD) study?

DESIGN

Data of 1038 female adolescents were used. Participants' baseline characteristics were obtained using self-reported questionnaires up to the age of 11-12 years, as well as the obstetric information of their mothers during pregnancy. Dysmenorrhoea was assessed at the age of 15-16 years, and was deemed to be present if an adolescent reported menstrual abdominal and/or back pain and therefore took medication and/or hormonal contraception. Using a backward selection approach, potential determinants of dysmenorrhoea were selected and multivariable associations were determined.

RESULTS

The overall prevalence of dysmenorrhoea was 49.5% among the participants. Intake of 3-4.5 sugar-sweetened beverages/day (P = 0.035) and higher gynaecological age (i.e. years since menarche) (P < 0.001) were significantly associated with higher occurrence of dysmenorrhoea in the final model, which explained 8.1% of the total variance in the occurrence of dysmenorrhoea. No significant associations were found between the occurrence of dysmenorrhoea and sociodemographic or psychosocial factors.

CONCLUSIONS

This investigation of various potential risk factors for dysmenorrhoea suggests that diet and reproductive factors are particularly important predictors of the occurrence of dysmenorrhoea among young adolescents. Specifically, intake of sugar-sweetened beverages and higher gynaecological age were predictive of the occurrence of dysmenorrhoea. Other lifestyle factors were also identified as possible risk factors. Using this knowledge, effective strategies can be developed to reduce the burden of dysmenorrhoea among adolescents, and to provide appropriate care for those suffering from the condition.

An Evaluation of Food and Nutrient Intake among Pregnant Women in The Netherlands: A Systematic Review

Nutritional deficiencies during pregnancy can have serious consequences for the health of the (unborn) child. This systematic review provides an updated overview of the available food and nutrient intake data for pregnant women in The Netherlands and an evaluation based on the current recommendations. Embase, MEDLINE, and national institute databases were used. Articles were selected if they had been published since 2008 and contained data on food consumption, nutrient intake, or the status of healthy pregnant women. A qualitative comparison was made with the 2021 Dutch Health Council recommendations and reference values. A total of 218 reports were included, representing 54 individual studies. Dietary assessments were primarily performed via food frequency questionnaires. Protein, vitamin A, thiamin, riboflavin, vitamin B₆, folate, vitamin B₁₂, vitamin C, iron, calcium, and magnesium intakes seemed to be adequate. For folate and vitamin D, supplements were needed to reach the recommended intake. The reasons for concern are the low intakes of fruits, vegetables, and (fatty) fish, and the intakes of alcohol, sugary drinks, and salt. For several foods and nutrients, no or limited intake data were found. High-quality, representative, and recent data are needed to evaluate the nutrient intake of pregnant women in order to make accurate assessments and evaluations, supporting scientific-based advice and national nutritional policies.

Differences in birthweight by maternal and paternal nativity status in Canada

BACKGROUND

Parental nativity, as well as duration of residence of foreign-born parents in the host country, has been shown to be associated with size at birth. However, most studies have focused on maternal nativity status only and have not accounted for important characteristics of both parents.

OBJECTIVE

To explore whether maternal and paternal nativity and length of residence (LOR) are independently associated with birthweight for gestational age in a representative sample of infants in Canada.

METHODS

We compared mean differences in sex- and gestational age-standardised birthweight z-score by nativity status of both parents in a nationally representative sample of 130,532 singleton infants born between May 2004 and May 2006 to mothers residing in Canada. We categorised parental nativity status into four groups (both parents Canada-born, mother only foreign-born, father only foreign-born and both parents foreign-born) and parents' LOR into three (both ≤10 years, only one parent ≤10 years and both >10 years). We estimated mean differences in birthweight z-score and their 95% confidence intervals in linear regression models adjusted for parity, parents' ages, education, ethnicity and marital status of the mother.

RESULTS

Compared with babies of Canada-born couples, those of two foreign-born parents had on average smaller birthweight z-score, -0.23 (95% CI -0.28, -0.25). However, after adjustment, the mean difference in z-score was -0.02 (95% CI -0.05, 0.00). Infants born to parents who had both resided in Canada for ≤10 years had a unadjusted mean difference in z-score of -0.27 (95% CI -0.29, -0.26), compared infants whose parents were both Canada-born, but the difference became negligible (-0.02, 95% CI -0.04, 0.01) after adjustment.

CONCLUSION

The birthweight differences by parental nativity or length of residence observed in our study population could be attributed to differences in the distribution of other parental characteristics that affect birthweight.

Growth patterns from birth to overweight at age 5-6 years of children with various backgrounds in socioeconomic status and country of origin: the ABCD study

INTRODUCTION

Children from minority groups are at increased risk of overweight. This study compared BMI growth patterns from birth onwards of boys and girls with overweight at 5-6 years, according to socioeconomic status (SES) and country of origin, in order to gain more insight into the critical periods of growth to overweight.

METHODS

A total of 3714 singletons of the multi-ethnic ABCD study were included. Within children with overweight at age 5-6 years (N = 487, prevalence boys: 11.6%, girls: 14.6%), BMI growth patterns from birth onwards (12.8 serial measurements; SD = 3.1) were compared between children from European (69.4%) and non-European mothers (30.6%), and between children from low (20.8%), mid (37.0%) or high SES (42.2%), based on maternal educational level.

RESULTS

BMI growth to overweight did not differ between children of European or non-European mothers, but it did differ according to maternal SES. Children with overweight in the low and mid SES group had a lower BMI in the first 2 years of life, an earlier adiposity rebound and increased in BMI more rapidly after age 2, resulting in a higher BMI at age 7 years compared to children with overweight in the high SES group [∆BMI (kg/m2 ) between high and low SES: boys 1.43(95%CI:0.16;3.01) and girls 1.91(0.55;3.27)].

CONCLUSION

Children with overweight from low SES have an early adiposity rebound and accelerated growth to a higher BMI at age 5-6 years compared to children with overweight from the high SES group. These results imply that timing of critical periods for overweight development is earlier in children with a low socioeconomic background as compared to other children.

Potential determinants during 'the first 1000 days of life' of sleep problems in school-aged children

STUDY OBJECTIVES

Early life determinants of sleep problems are mostly unknown. The first 1000 days of life (ie, the time between conception and a child's second birthday) is a period where the foundations for optimum health, growth and neurodevelopment are established. The aim of this explorative study is to identify potential early life determinants of sleep problems at age 7-8 years.

METHODS

Data from the Amsterdam Born Children and their Development cohort study (n = 2746) were analyzed. Sleep problems at age 7-8 years were reported by the caregiver in the 'Child Sleep Habits Questionnaire'. A higher total score indicates more sleep problems. After multiple imputation (n = 20), we studied multivariable associations between all potential determinants and sleep problems using regression analysis.

RESULTS

A higher pre-pregnancy body mass index (BMI) was associated with more sleep problems at age 7-8 years [β 0.12 (95% CI 0.05, 0.18)]. Children of mothers with symptoms of anxiety during pregnancy [β 0.06 (95% CI 0.03, 0.09)] and infancy period [β 0.04 (95% CI 0.00, 0.07)] had more sleep problems. Children of mothers drinking ≥1 glass of alcohol a day around 14 weeks of gestation had a 2 points higher sleep problem score [β 2.55 (95% CI 0.21, 4.89)] and children of mothers smoking ≥1 cigarette per day in that period had a one point higher score [β 1.07 (95% CI 0.10, 2.03)]. Infants with relative weight loss (delta BMI-SD) had a higher sleep problem score during childhood [β -0.32 (95%CI -0.60, -0.04)].

CONCLUSIONS

We identified several potential determinants during pregnancy and infancy associated with childhood sleeping problems. We encourage further research into these and other potential determinants to replicate results and to identify underlying mechanisms.

Offspring birthweight and placental weight in immigrant women from conflict-zone countries; does length of residence in the host country matter? A population study in Norway

INTRODUCTION

We aimed to estimate differences in offspring birthweight and placental weight between Norwegian women and immigrants in Norway from countries with armed conflicts. We also studied whether length of residence in Norway was associated with offspring birthweight and placental weight.

MATERIAL AND METHODS

We included in our study all singleton births in Norway at gestational week 28 or beyond during the years 1999-2014, to mothers who were born in Somalia, Afghanistan, Iraq (total immigrants n = 18 817), or Norway (n = 668 439). Data were obtained from The Medical Birth Registry of Norway and the Central Person Registry of Norway. We estimated the differences between Norwegian and immigrant women in mean offspring birthweight and mean placental weight by applying linear regression analyses. Adjustments were made for maternal age, parity, year of delivery, gestational age at delivery, preeclampsia, and diabetes.

RESULTS

The immigrant women had 206 g (95% CI 199 to 213 g) lower mean offspring birthweight and 16 g (95% CI 14 to 18 g) lower mean placental weight than Norwegian women. Immigrant women with ≥5 years of residence in Norway had higher offspring birthweight (40 g) and higher placental weight (17 g) than immigrant women with <5 years of residence.

CONCLUSIONS

Immigrant mothers from Somalia, Afghanistan, and Iraq gave birth to infants and placentas with lower weight than Norwegian women. However, the difference between Norwegian women and immigrant women was reduced by length of residence in Norway.

Food Consumption, Nutrient Intake and Status during the First 1000 days of Life in the Netherlands: a Systematic Review

Adequate nutrition is essential for growth and development in early life. Nutritional data serves as a basis for national nutritional guidelines and policies. Currently, there is no insight into the availability of such data during the first 1000 days of life. Therefore, a systematic review was performed, following the PRISMA reporting guideline, to identify studies on food consumption, nutrient intake or status in the Netherlands. Potential gaps were identified, and the quality of the studies is discussed. The databases Embase and Medline were used, as well as databases from national institutes. Articles published in 2008-2018 were screened by two independent reviewers. In total 601 articles were identified, of which 173 were included. For pregnant women, 32 studies were available with nutritional data, for young children 40 studies were identified. No studies were available for breastfeeding women. A large variety of foods and nutrients were assessed, however certain nutrients were lacking (e.g., vitamin K). Overall, the studies had methodological limitations, making the data unsuitable to assess nutrient inadequacies. There is a need for recent, high quality nutritional research to strengthen the understanding of the nutritional needs and deficiencies during early life, and is fundamental for national guidelines and policies.

One size does not fit all: Examining ethnicity in gestational weight gain guidelines

Pregnancy-related metrics vary by race/ethnicity, yet most gestational weight gain (GWG) guidelines are ethnicity-blind. We estimated small-for-gestational age (SGA) risk in a Japanese population, examining GWG adequacy categorized by Institute of Medicine (IOM) and Japanese guidelines in male (N  = 192) and female (N = 191) full-term singleton infants. For predicting SGA, IOM guidelines had high sensitivity ( ≥ 0.75), but low specificity ( ≤ 0.25); Japanese guidelines had high specificity ( ≥ 0.80) but low sensitivity ( ≤ 0.50). GWG guidelines' implicit notions of Caucasian-Americans as optimal may lead to 'One Size Fits All' recommendations that can obscure important biocultural factors contributing to maternal child health outcomes.

Vitamin D levels during pregnancy and associations with birth weight and body composition of the newborn: a longitudinal multiethnic population-based study

We investigated associations between serum 25-hydroxyvitamin D (25(OH)D) in pregnancy and birth weight and other neonatal anthropometric measures. The present study was a population-based, multiethnic cohort study of 719 pregnant women (59 % ethnic minorities) in Oslo, Norway, delivering a singleton neonate at term and with birth weight measurements. In a representative sample, anthropometric measurements were taken. Maternal 25(OH)D was measured at gestational weeks 15 and 28. Women with 25(OH)D <37 nmol/l were recommended vitamin D3 supplementation. Separate linear regression analyses were performed to model the associations between 25(OH)D and each of the outcomes: birth weight, crown-heel length, head circumference, abdominal circumference, sum of skinfolds, mid-upper arm circumference and ponderal index. In early pregnancy, 51 % of the women were vitamin D deficient (25(OH)D<50 nmol/l). In univariate analyses and in models adjusting for maternal age, parity, education, prepregnancy BMI, season, gestational age and neonate sex, maternal 25(OH)D was significantly associated with birth weight, head circumference, abdominal circumference and ponderal index (P<0·05 for all), when used as a continuous variable and categorised (consistently low, consistently high, increasing and decreasing level). However, after adjusting for ethnicity, 25(OH)D was no longer associated with any of the outcomes. Sex-specific associations for abdominal circumference and sum of skinfolds were found (P for interaction<0·05). In conclusion, in a multiethnic cohort of pregnant women with high prevalence of vitamin D deficiency, we found no independent relation between maternal vitamin D levels and any of the neonatal anthropometric measures, and the strong association between ethnicity and neonatal outcomes was not affected by maternal vitamin D status.

The likeness of fetal growth and newborn size across non-isolated populations in the INTERGROWTH-21st Project: the Fetal Growth Longitudinal Study and Newborn Cross-Sectional Study

BACKGROUND

Large differences exist in size at birth and in rates of impaired fetal growth worldwide. The relative effects of nutrition, disease, the environment, and genetics on these differences are often debated. In clinical practice, various references are often used to assess fetal growth and newborn size across populations and ethnic origins, whereas international standards for assessing growth in infants and children have been established. In the INTERGROWTH-21(st) Project, our aim was to assess fetal growth and newborn size in eight geographically defined urban populations in which the health and nutrition needs of mothers were met and adequate antenatal care was provided.

METHODS

For this study, fetal growth and newborn size were measured in two INTERGROWTH-21(st) component studies using prespecified markers and the same methods, equipment, and selection criteria. In the Fetal Growth Longitudinal Study (FGLS), we studied educated, affluent, healthy women, with adequate nutritional status who were at low risk of intrauterine growth restriction. The primary markers of fetal growth were ultrasound measurements of fetal crown-rump length at less than 14 weeks and 0 days of gestation and fetal head circumference from 14 weeks and 0 days to 40 weeks and 0 days of gestation, and birthlength for newborn size. In the concomitant, population-based Newborn Cross-Sectional Study (NCSS), we measured birthlength in all newborn babies from the eight geographically defined urban populations with the same methods, instruments, and staff as in FGLS. From this large NCSS cohort, we selected an FGLS-like subpopulation to match FGLS with the same eligibility criteria.

FINDINGS

Between May 14, 2009, and Aug 2, 2013, we enrolled 4607 women in FGLS and 59 137 women in NCSS. From NCSS, 20 486 (34·6%) women met the FGLS eligibility criteria, and constituted the FGLS-like subpopulation. With variance component analysis, only between 1·9% and 3·5% of the total variability in crown-rump length, fetal head circumference, and newborn birthlength could be attributed to between-site differences. With standardised site effect analysis in 16 gestational age windows from 9 weeks and 0 days of gestation to birth for the three measures (128 comparisons), only one was marginally higher than 0·5 SD of the standardised site difference range. Sensitivity analyses, excluding individual populations in turn from the pooling of all-site centiles across gestational ages, showed no noticeable effect on the 3rd, 50th, and 97th centiles derived from the remaining populations. Our populations were consistent at birth with those in the WHO Multicentre Growth Reference Study (MGRS). The mean birthlength for term newborn babies in that study was 49·5 cm (SD 1·9), which was very similar to that in the FGLS cohort (49·4 cm [1·9]) and the NCSS derived FGLS-like subpopulation (49·3 cm [1·8]).

INTERPRETATION

Fetal growth and newborn length are similar across diverse geographical settings when mothers' nutritional and health needs are met, and environmental constraints on growth are low. The findings for birthlength are in strong agreement with those of the WHO MGRS. These results provide the conceptual frame to create international standards for growth from conception to newborn baby, which will extend the present infant to childhood WHO MGRS standards.

FUNDING

Bill & Melinda Gates Foundation.

Relation of maternal hypertension with infant growth in a prospective birth cohort: the ABCD study

The aim of this study was to investigate the assumed positive association of pre-existent and pregnancy-induced hypertension with the offspring's weight and length gain in the first 14 months of life. We studied 3994 pregnant women and their offspring in a prospective community-based cohort study, starting between 2003 and 2004 (Amsterdam Born Children and their Development, ABCD study). Questionnaires obtaining information about hypertension during pregnancy were completed, and this was complemented with additional information from the obstetric caregiver. Anthropometry of the offspring was followed during the first 14 months of life. Main outcome measures were presence or absence of growth acceleration in weight or length (normal: ΔSDS ⩽ 0.67 v. growth acceleration: ΔSDS > 0.67). The relation between hypertension during pregnancy and weight and length gain was addressed by logistic regression analyses. We found that pre-existent hypertension was related to growth acceleration in weight and length. After correction for birth weight and pregnancy duration, the effect remained significant for growth acceleration in weight (OR 1.89; 95% CI 1.21-2.97; P < 0.01). Pregnancy-induced hypertension showed similar results, although correction for birth weight and pregnancy duration rendered the associations non-significant. In conclusion, infants of women with pre-existent hypertension during pregnancy more frequently have growth acceleration in weight and length, and yet the mechanisms acting on postnatal growth appear to be different.

Ethnic differences in neonatal body composition in a multi-ethnic population and the impact of parental factors: a population-based cohort study

BACKGROUND

Neonates from low and middle income countries (LAMIC) tend to have lower birth weight compared with Western European (WE) neonates. Parental height, BMI and maternal parity, age and educational level often differ according to ethnic background, and are associated with offspring birth weight. Less is known about how these factors affect ethnic differences in neonatal body composition.

OBJECTIVES

To explore differences in neonatal body composition in a multi-ethnic population, and the impact of key parental factors on these differences.

METHODS

A population-based cohort study of pregnant mothers, fathers and their offspring, living in Oslo, Norway. Gender- and gestational-specific z-scores were calculated for several anthropometric measurements, with the neonates of WE ethnic origin as reference. Mean z-scores for neonates with LAMIC origin, and their parents, are presented as outcome variables.

RESULTS

537 singleton, term neonates and their parents were included. All anthropometric measurements were smaller in neonates with LAMIC origin. Abdominal circumference and ponderal index differed the most from WE (mean z-score: -0.57 (95% CI:-0.69 to -0.44) and -0.54 (-0.66 to -0.44), and remained so after adjusting for parental size. Head circumference and skin folds differed less, and length the least (-0.21 (-0.35 to -0.07)). These measures became comparable to WEs when adjusted for parental factors.

CONCLUSIONS

LAMIC origin neonates were relatively "thin-fat", as indicated by reduced AC and ponderal index and relatively preserved length and skin folds, compared with neonates with WE origin. This phenotype may predispose to type 2 diabetes.

Adiposity and hyperglycaemia in pregnancy and related health outcomes in European ethnic minorities of Asian and African origin: a review

BACKGROUND

Ethnic minorities in Europe have high susceptibility to type 2 diabetes (T2DM) and, in some groups, also cardiovascular disease (CVD). Pregnancy can be considered a stress test that predicts future morbidity patterns in women and that affects future health of the child.

OBJECTIVE

TO REVIEW ETHNIC DIFFERENCES IN: 1) adiposity, hyperglycaemia, and pre-eclampsia during pregnancy; 2) future risk in the mother of obesity, T2DM and CVD; and 3) prenatal development and possible influences of maternal obesity, hyperglycaemia, and pre-eclampsia on offspring's future disease risk, as relevant for ethnic minorities in Europe of Asian and African origin.

DESIGN

Literature review.

RESULTS

Maternal health among ethnic minorities is still sparsely documented. Higher pre-pregnant body mass index (BMI) is found in women of African and Middle Eastern descent, and lower BMI in women from East and South Asia compared with women from the majority population. Within study populations, risk of gestational diabetes mellitus (GDM) is considerably higher in many minority groups, particularly South Asians, than in the majority population. This increased risk is apparent at lower BMI and younger ages. Women of African origin have higher risk of pre-eclampsia. A GDM pregnancy implies approximately seven-fold higher risk of T2DM than normal pregnancies, and both GDM and pre-eclampsia increase later risk of CVD. Asian neonates have lower birth weights, and mostly also African neonates. This may translate into increased risks of later obesity, T2DM, and CVD. Foetal overgrowth can promote the same conditions. Breastfeeding represents a possible strategy to reduce risk of T2DM in both the mother and the child.

CONCLUSIONS

Ethnic minority women in Europe with Asian and African origin and their offspring seem to be at increased risk of T2DM and CVD, both currently and in the future. Pregnancy is an important window of opportunity for short and long-term disease prevention.

Social deprivation and adverse perinatal outcomes among Western and non-Western pregnant women in a Dutch urban population

Social deprivation is considered a key factor in adverse perinatal outcomes. Rotterdam, the second largest city in The Netherlands, has large inequalities in perinatal health and a high number of deprived neighbourhoods. Social deprivation is measured here through a composite variable: 'Social Index' (SI). We studied the impact of the SI (2008-2009; 5 categories) in terms of perinatal mortality, congenital anomalies, preterm birth, small for gestational age (SGA) and low 5-minute Apgar score as registered in The Netherlands Perinatal Registry (Rotterdam 2000-2007, n = 56,443 singleton pregnancies). We applied ethnic dichotomisation as Western (European/North-American/Australian) vs. Non-Western (all others) ethnicity was expected to interact with the impact of SI. Tests for trend and multilevel regression analysis were applied. Gradually decreasing prevalence of adverse perinatal outcomes was observed in Western women from the lowest SI category (low social quality) to the highest SI category (high social quality). In Western women the low-high SI gradient for prevalence of spontaneous preterm birth (per 1000) changed from 57.2 to 34.1, for iatrogenic preterm birth from 35.2 to 19.0, for SGA from 119.6 to 59.4, for low Apgar score from 10.9 to 8.2, and for perinatal mortality from 14.9 to 7.6. These trends were statistically confirmed by Chi2-tests for trend (p < 0.001). For non-Western women such trends were absent. These strong effects for Western women were confirmed by significant odds ratios for almost all adverse perinatal outcomes estimated from multilevel regression analysis. We conclude social deprivation to play a different role among Western vs. non-Western women. Our results suggest that improvements in social quality may improve perinatal outcomes in Western women, but alternative approaches may be necessary for non-Western groups. Suggested explanations for non-Western 'migrant' groups include the presence of 'protective' effects through knowledge systems or intrinsic resilience. Implications concern both general and targeted policies.

Pregnancy outcomes of women with and without a history of anorexia nervosa

BACKGROUND

When women have a history of anorexia nervosa (AN), the advice given about becoming pregnant, and about the management of pregnancies, has usually been cautious. This study compared the pregnancy outcomes of women with and without a history of AN.

METHOD

Women with a confirmed diagnosis of AN who had presented to psychiatric services in North East Scotland from 1965 to 2007 were identified. Those women with a pregnancy recorded in the Aberdeen Maternal and Neonatal Databank (AMND) were each matched by age, parity and year of delivery of their first baby with five women with no history of AN. Maternal and foetal outcomes were compared between these two groups of women. Comparisons were also made between the mothers with a history of AN and all other women in the AMND.

RESULTS

A total of 134 women with a history of AN delivered 230 babies and the 670 matched women delivered 1144 babies. Mothers with AN delivered lighter babies but this difference did not persist after adjusting for maternal body mass index (BMI) in early pregnancy. Standardized birthweight (SBW) scores suggested that the AN mothers were more likely to produce babies with intrauterine growth restriction (IUGR) [relative risk (RR) 1.54, 95% confidence interval (CI) 1.11-2.13]. AN mothers were more likely to experience antepartum haemorrhage (RR 1.70, 95% CI 1.09-2.65).

CONCLUSIONS

Mothers with a history of AN are at increased risk of adverse pregnancy outcomes. The magnitude of these risks is relatively small and should be appraised holistically by psychiatric and obstetric services.

Suboptimal maternal vitamin D status and low education level as determinants of small-for-gestational-age birth weight

PURPOSE

This study aimed firstly to investigate the contribution of maternal 25(OH) vitamin D to the association of maternal education and small-for-gestational-age birth weight (SGA) and secondly to examine whether the contribution of 25(OH) vitamin D differs by overweight, season, and maternal smoking.

METHODS

Logistic regression analysis was carried out in this study, using data of 2,274 pregnant women of Dutch ethnicity from the ABCD study, a population-based cohort study in the Netherlands. Maternal 25(OH) vitamin D was measured in early pregnancy. Stratified analyses were conducted for overweight, season of blood sampling, and smoking.

RESULTS

Low-educated women had lower 25(OH) vitamin D levels compared to high-educated women, and women in the lowest 25(OH) vitamin D quartile had a higher risk of SGA offspring. In addition, low-educated women had a higher risk of SGA offspring (OR 1.95 [95% CI: 1.20-3.14]). This association decreased with 7% after adjustment for 25(OH) vitamin D (OR 1.88 [95% CI 1.16-3.04]). In stratified analyses, adjustment for 25(OH) vitamin D resulted in a decrease in OR of about 17% in overweight women and about 15% in women who conceived in wintertime.

CONCLUSIONS

25(OH) vitamin D appears to be a modifiable contributor to the association between low maternal education and SGA offspring, particularly in overweight women and women who conceived in the winter period. In those women, increasing the intake of vitamin D, either through dietary adaptation or through supplementation in order to achieve the recommendation, could be beneficial.

Contribution of overweight and obesity to the occurrence of adverse pregnancy outcomes in a multi-ethnic cohort: population attributive fractions for Amsterdam

OBJECTIVE

To estimate the contribution of pre-pregnancy excessive weight to the occurrence of adverse pregnancy outcomes and to detect the differences in these contributions between different ethnic groups.

DESIGN

Prospective multi-ethnic community-based cohort study.

SETTING

The prevalence of excessive weight is increasing and in general higher in immigrant groups in many industrialised countries. Maternal excessive weight, like smoking during pregnancy, is an important risk factor for adverse pregnancy outcomes.

POPULATION

A total of 8266 pregnant women, living in the Netherlands, were included in the ABCD study between January 2003 and March 2004.

METHODS

After applying the exclusion criteria, the analysis included 7871 pregnancies. Binomial log-linear regression analyses were performed to estimate relative risks (RRs) expressing the association between overweight/obesity and small-for-gestational-age (SGA), large-for-gestational-age (LGA), preterm birth (PTB; <37 weeks of gestation) and extreme PTB (<32 weeks of gestation), controlling for parity, maternal age, education level and smoking. Next, the RRs were used to estimate population attributive fractions (PAF) for Amsterdam and separately for several ethnic groups.

MAIN OUTCOME MEASURES

The RRs and PAFs.

RESULTS

The PAFs for overweight/obesity were: SGA -4.9%, LGA 15.3%, PTB 6.6% and extreme PTB 22.0%. In absolute terms, this corresponds to -47 SGA infants, 126 LGA infants, 35 PTB and 20 extreme PTB per year in Amsterdam. Except for SGA, these PAFs were higher than those for smoking (6.2%, -3.9%, 5.5% and 10.6%, respectively). The contribution of overweight/obesity to LGA and PTB was higher in non-Western immigrant groups.

CONCLUSIONS

Overweight/obesity has become an important contributor to the occurrence of adverse pregnancy outcomes in Amsterdam. For most outcomes, these contributions are larger than those for smoking. Development of special obesity prevention programmes for young women is required, especially focused on immigrant groups.

Comparison of growth between native and immigrant infants between 0-3 years from the Dutch ABCD cohort

BACKGROUND

In the Netherlands separate reference charts have been developed for native and immigrant groups to deal with differences in growth patterns in later childhood. The use of these charts, however, is complicated by methodological issues; they do not represent all large Dutch immigrant groups in separate charts despite the differences that have been suggested and the evidence of ethnic disparities in growth dates back to 1997.

AIM

Anthropometric measurements from a contemporary multi-ethnic cohort study were created to quantify differences in childhood growth by creating growth charts, separately for boys and girls between the ages of 0-3 years.

SUBJECTS AND METHODS

The infants modelled in the charts had a mother born in the Netherlands (n = 3107), Suriname (n = 225), Turkey (n = 203) and Morocco (n = 336). Charts with and without correction for country of origin of the mother were created by using the LMST method.

RESULTS

All models including the covariate country of origin of the mother fitted the data better (p < 0.0005), but the observed differences were small.

CONCLUSION

Most remarkable differences were found in the BMI and weight measurements for age charts. Especially girls from mothers born in Turkey and Morocco had an increasingly heavier weight for their age than girls from mothers born in the Netherlands.

Process evaluation of a multiple risk factor perinatal programme for a hard-to-reach minority group

AIM

This article is a report of an evaluation of a multiple risk factor perinatal programme tailored to ethnic Turkish women in the Netherlands.

BACKGROUND

The programme was directed at multiple risk factors and aimed at improving maternal lifestyle, infant care practices and psychosocial health during pregnancy and after delivery. The programme was carried out by ethnic Turkish community health workers in collaboration with midwives and physiotherapists.

METHODS

Our multiple case study included three Parent-Child Centres providing integrated maternity and infant care. Participants (n = 119) were first and second generation pregnant ethnic Turkish women with relatively unfavourable risk profiles. Data were collected between 2005 and 2008 using mixed methods, including field notes, observations and recordings of group classes, attendance logs, semi-structured individual interviews, a focus group interview, and structured questionnaires.

FINDINGS

Most participants (82%) were first generation ethnic Turkish; 47% had a low educational level; 43% were pregnant with their first child; and 34% had a minimal knowledge of the Dutch language. The community health workers' Turkish background was vital in overcoming cultural and language barriers and creating a confidential atmosphere. Participants, midwives and health workers were positive about the programme. Midwives also observed improvements of knowledge and self-confidence amongst the participants. The integration of the community health workers into midwifery practices was crucial for a successful programme implementation.

CONCLUSIONS

A culturally sensitive perinatal programme is able to gain access to a hard-to-reach minority group at increased risk for poor perinatal health outcomes. Such a programme may be well received and potentially effective.

Residential proximity to heavy traffic and birth weight in Shizuoka, Japan

An association between exposure to traffic-related air pollution and reduced birth weight has been suggested. However, previous studies have failed to adjust for maternal size, which is an indicator of individual genetic growth potential. Therefore, we evaluated the association of air pollution with birth weight, term low birth weight (term-LBW), and small for gestational age (SGA), with adjustment for maternal size. Individual data were extracted from a database that is maintained by a maternal and perinatal care center in Shizuoka, Japan. We identified liveborn singleton births (n=14,204). Using geocoded residential information, each birth was assigned a number of traffic-based exposure indicators: distance to a major road; distance-weighted traffic density; and estimated concentration of nitrogen dioxide by land use regression. The multivariate adjusted odds ratios and their 95% confidence intervals (CIs) for the associations between exposure indicators and outcomes were then estimated using logistic regression models. Overall, exposure indicators of air pollution showed no clear pattern of association. Although there are many limitations, we did not find clear associations between birth-weight-related outcomes and the three markers of traffic-related air pollution.

Maternal depressive symptoms in relation to perinatal mortality and morbidity: results from a large multiethnic cohort study

OBJECTIVE

To explore whether 1) maternal depressive symptoms during pregnancy are associated with preterm birth (PTB), small for gestational age (SGA), a low Apgar score and child loss; 2) maternal smoking mediates the associations; and 3) the associations differ by ethnic background.

METHODS

Pregnant women in Amsterdam were approached during their first prenatal visit to participate in the Amsterdam Born Children and their Development study. They filled out a questionnaire covering sociodemographic data, life-style, and (psychosocial) health. Depressive symptoms were assessed with the Center for Epidemiologic Studies Depression scale. The baseline sample consisted of 8,052 women; the main ethnic groups were: Dutch, Creole, Turkish, and Moroccan.

RESULTS

The prevalence of perinatal outcomes was: 5.4% (PTB); 12.3% (SGA); l 1.5% (low Apgar score); and 1.4% (child loss). The prevalence of high depressive symptomatology was 30.6%. After adjustment for maternal age, parity, education, ethnicity, prepregnancy body mass index, hypertension, alcohol and drug use, and a small mediation effect of maternal smoking, high versus low levels of depressive symptoms were associated with SGA (odds ratio [OR], 1.19; p = .02) and a low Apgar score (OR, 1.74; p = .01), but not with PTB (OR, 1.16; p = .18) and child loss (OR, 1.28; p = .24). Stratified analyses by ethnic background showed a tendency toward higher risks, although insignificant, among Creole women.

CONCLUSIONS

Several pathways may explain the detrimental effects of maternal depressive symptomatology on perinatal health outcomes, including a psychoendocrinological pathway involving the hormone cortisol or mediation effects by maternal risk behaviors. Further research should explore the underlying pathways, in particular among ethnic subgroups.

Maternal cortisol and offspring birthweight: results from a large prospective cohort study

Maternal psychosocial problems may affect fetal growth through maternal cortisol. This large prospective cohort study examined among 2810 women (1) the association of maternal cortisol levels with offspring birthweight and small for gestational age (SGA) risk and (2) the mediating role of maternal cortisol on the relation between maternal psychosocial problems and fetal growth. Pregnant women in Amsterdam were approached during their first prepartum visit (+/-13 weeks gestation). Total maternal cortisol level was determined in serum and maternal psychosocial indicators were collected through a questionnaire. Maternal cortisol levels were negatively related to offspring birthweight (B=-0.35; p<.001) and positively to SGA (OR=1.00; p=.027); after adjustment (for gestational age at birth, infant gender, ethnicity, maternal age, parity, BMI, and smoking), these effects were statistically insignificant. Post hoc analysis revealed a moderation effect by time of day: only in those women who provided a blood sample < or =09:00h (n=94), higher maternal cortisol levels were independently related to lower birthweights (B=-0.94; p=.025) and a higher SGA risk (OR=1.01; p=.032). Maternal psychosocial problems were not associated with cortisol levels. In conclusion, although an independent association between maternal cortisol levels in early pregnancy and offspring birthweight and SGA risk was not observed, exploratory post hoc analysis suggested that the association was moderated by time of day, such that the association was only present in the early morning. The hypothesis that maternal psychosocial problems affect fetal growth through elevated maternal cortisol levels could not be supported.

Birth weight and body composition of neonates born to Caucasian compared with African-American mothers

OBJECTIVE

To estimate whether neonates of African-American women have lower birth weights because of either decreased lean body mass or fat mass.

METHODS

A secondary analysis of a cohort of 104 African-American and 274 Caucasian term, singleton, healthy pregnancies. Women with existing or gestational diabetes were excluded. Neonatal body composition was estimated using anthropometric measurements.

RESULTS

There were significant differences in maternal age (29.5 compared with 25.8, P<.001), prepregnancy body mass index (26.2 compared with 30.9 kg/m, P<.001), and weight gain during pregnancy (15.2 compared with 13.4 kg, P=.03) in Caucasian compared with African-American women, respectively. After adjusting for these factors, African-American women's neonates had significantly lower birth weights (3.20 compared with 3.36 kg, P=.003), less lean body mass (2.80 compared with 2.94 kg, P=.002), but no difference in fat mass (392 compared with 417 g, P=.078).

CONCLUSION

Decreased birth weight in African-American neonates is due to lower lean body mass and not a difference in adiposity.

Maternal early pregnancy vitamin D status in relation to fetal and neonatal growth: results of the multi-ethnic Amsterdam Born Children and their Development cohort

Low vitamin D levels during pregnancy may account for reduced fetal growth and for altered neonatal development. The present study explored the association between maternal vitamin D status measured early in pregnancy and birth weight, prevalence of small-for-gestational-age (SGA) infants and postnatal growth (weight and length), as well as the potential role of vitamin D status in explaining ethnic disparities in these outcomes. Data were derived from a large multi-ethnic cohort in The Netherlands (Amsterdam Born Children and their Development (ABCD) cohort), and included 3730 women with live-born singleton term deliveries. Maternal serum vitamin D was measured during early pregnancy (median 13 weeks, interquartile range: 12-14), and was labelled 'deficient' ( <or= 29.9 nmol/l), 'insufficient' (30-49.9 nmol/l) or 'adequate' ( >or= 50 nmol/l). Six ethnic groups were distinguished: Dutch, Surinamese, Turkish, Moroccan, other non-Western and other Western. Associations with neonatal outcomes were analysed using multivariate regression analyses. Results showed that compared with women with adequate vitamin D levels, women with deficient vitamin D levels had infants with lower birth weights ( - 114.4 g, 95 % CI - 151.2, - 77.6) and a higher risk of SGA (OR 2.4, 95 % CI 1.9, 3.2). Neonates born to mothers with a deficient vitamin D status showed accelerated growth in weight and length during the first year of life. Although a deficient vitamin D status influenced birth weight, SGA risk and neonatal growth, it played a limited role in explaining ethnic differences. Although vitamin D supplementation might be beneficial to those at risk of a deficient vitamin D status, more research is needed before a nationwide policy on the subject can be justified.

Psychosocial problems and continued smoking during pregnancy

The present study examined the association of several psychosocial problems with continued smoking during pregnancy. Based on a population-based cohort study among pregnant women in Amsterdam (n=8266), women who smoked before pregnancy were included in this study (n=1947). Women completed a questionnaire around the 12th week of gestation. Based on whether they smoked in the past week, participants were categorized as quitters or non-quitters. Depressive symptoms (CES-D), anxiety (STAI), pregnancy-related anxiety, job strain, parenting stress and physical/sexual violence were measured. Multiple logistic regression analyses were performed. After adjustment for sociodemographic and smoking-related covariates, low and high levels of pregnancy-related anxiety, exposure to physical/sexual violence, and high job strain were significantly associated with continued smoking during pregnancy. Intensive and comprehensive smoking cessation programs are required for pregnant women, which includes the management of psychosocial problems.

Ethnic differences in early pregnancy maternal n-3 and n-6 fatty acid concentrations: an explorative analysis

Ethnicity-related differences in maternal n-3 and n-6 fatty acid status may be relevant to ethnic disparities in birth outcomes observed worldwide. The present study explored differences in early pregnancy n-3 and n-6 fatty acid composition of maternal plasma phospholipids between Dutch and ethnic minority pregnant women in Amsterdam, the Netherlands, with a focus on the major functional fatty acids EPA (20 : 5n-3), DHA (22 : 6n-3), dihomo-gamma-linolenic acid (DGLA; 20 : 3n-6) and arachidonic acid (AA; 20 : 4n-6). Data were derived from the Amsterdam Born Children and their Development (ABCD) cohort (inclusion January 2003 to March 2004). Compared with Dutch women (n 2443), Surinamese (n 286), Antillean (n 63), Turkish (n 167) and Moroccan (n 241) women had generally lower proportions of n-3 fatty acids (expressed as percentage of total fatty acids) but higher proportions of n-6 fatty acids (general linear model; P < 0.001). Ghanaian women (n 54) had higher proportions of EPA and DHA, but generally lower proportions of n-6 fatty acids (P < 0.001). Differences were most pronounced in Turkish and Ghanaian women, who, by means of a simple questionnaire, reported the lowest and highest fish consumption respectively. Adjustment for fish intake, however, hardly attenuated the differences in relative EPA, DHA, DGLA and AA concentrations between the various ethnic groups. Given the limitations of this observational study, further research into the ethnicity-related differences in maternal n-3 and n-6 fatty acid patterns is warranted, particularly to elucidate the explanatory role of fatty acid intake v. metabolic differences.