Global, regional, and national estimates of levels of preterm birth in 2014: a systematic review and modelling analysis

Impact of preterm birth on brain development and long-term outcome: protocol for a cohort study in Scotland

INTRODUCTION

Preterm birth is closely associated with altered brain development and is a leading cause of neurodevelopmental, cognitive and behavioural impairments across the life course. We aimed to investigate neuroanatomic variation and adverse outcomes associated with preterm birth by studying a cohort of preterm infants and controls born at term using brain MRI linked to biosamples and clinical, environmental and neuropsychological data.

METHODS AND ANALYSIS

Theirworld Edinburgh Birth Cohort is a prospective longitudinal cohort study at the University of Edinburgh. We plan to recruit 300 infants born at <33 weeks of gestational age (GA) and 100 healthy control infants born after 37 weeks of GA. Multiple domains are assessed: maternal and infant clinical and demographic information; placental histology; immunoregulatory and trophic proteins in umbilical cord and neonatal blood; brain macrostructure and microstructure from structural and diffusion MRI (dMRI); DNA methylation; hypothalamic-pituitary-adrenal axis activity; social cognition, attention and processing speed from eye tracking during infancy and childhood; neurodevelopment; gut and respiratory microbiota; susceptibility to viral infections; and participant experience. Main analyses include creation of novel methods for extracting information from neonatal structural and dMRI, regression analyses of predictors of brain maldevelopment and neurocognitive outcome associated with preterm birth, and determination of the quantitative predictive performance of MRI and other early life factors for childhood outcome.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the National Research Ethics Service (NRES), South East Scotland Research Ethics Committee (NRES numbers 11/55/0061 and 13/SS/0143 (phase I) and 16/SS/0154 (phase II)), and NHS Lothian Research and Development (2016/0255). Results are disseminated through open access journals, scientific meetings, social media, newsletters anda study website (www.tebc.ed.ac.uk), and we engage with the University of Edinburgh public relations and media office to ensure maximum publicity and benefit.

Altered productions of prostaglandins and prostamides by human amnion in response to infectious and inflammatory stimuli identified by mutliplex mass spectrometry

INTRODUCTION

Prostaglandins are critical for the onset and progression of labor in mammals, and are formed by the metabolism of arachidonic acid. The products of arachidonic acid, 2-arachidonoylglycerol (2-AG), and anandamide (AEA) have a similar lipid back bone but differing polar head groups, meaning that identification of these products by immunoassay can be difficult.

MATERIALS AND METHODS

In the current study, we present the use of mass spectrometry as multiplex method of identifying the specific end products of arachidonic and anandamide metabolism by human derived amnion explants treated with either an infectious agent (LPS) or inflammatory mediator (IL-1β or TNF-α).

RESULTS

Human amnion tissue explants treated with LPS, IL-1β, or TNF-α increased production of prostaglandin E₂ (PGE₂; p < 0.05) but decreased PGFM. Overall, PGE₂ production was greater compared to the other prostaglandins and prostamides irrespective of treatment.

CONCLUSIONS

The findings of the current study are in keeping with the literature which describes amnion tissues as predominantly producing PGE₂. The use of mass spectrometry for the differential identification of prostaglandins, prostamides, and other eicosanoids may help better elucidate mechanisms of preterm labor, and lead to new targets for the prediction of risk for preterm labor and/or birth.

Preventing CKD in Developed Countries

Chronic kidney disease (CKD) is an important public health concern in developed countries because of both the number of people affected and the high cost of care when prevention strategies are not effectively implemented. Prevention should start at the governance level with the institution of multisectoral polices supporting sustainable development goals and ensuring safe and healthy environments. Primordial prevention of CKD can be achieved through implementation of measures to ensure healthy fetal (kidney) development. Public health strategies to prevent diabetes, hypertension, and obesity as risk factors for CKD are important. These approaches are cost-effective and reduce the overall noncommunicable disease burden. Strategies to prevent nontraditional CKD risk factors, including nephrotoxin exposure, kidney stones, infections, environmental exposures, and acute kidney injury (AKI), need to be tailored to local needs and epidemiology. Early diagnosis and treatment of CKD risk factors such as diabetes, obesity, and hypertension are key for primary prevention of CKD. CKD tends to occur more frequently and to progress more rapidly among indigenous, minority, and socioeconomically disadvantaged populations. Special attention is required to meet the CKD prevention needs of these populations. Effective secondary prevention of CKD relies on screening of individuals at risk to detect and treat CKD early, using established and emerging strategies. Within high-income countries, barriers to accessing effective CKD therapies must be recognized, and public health strategies must be developed to overcome these obstacles, including training and support at the primary care level to identify individuals at risk of CKD, and appropriately implement clinical practice guidelines.

The impact of maternal prepregnancy impaired fasting glucose on preterm birth and large for gestational age: a large population-based cohort study

BACKGROUND

The impact of maternal prepregnancy impaired fasting glucose on preterm birth and large for gestational age has been poorly understood.

OBJECTIVES

We aimed to estimate the impact of prepregnancy impaired fasting glucose defined by the World Health Organization cut point on the risk of preterm birth and large for gestational age and to investigate whether the World Health Organization cut point of impaired fasting glucose was appropriate for identifying women at risk of preterm birth and large for gestational age among the Chinese population.

STUDY DESIGN

This was a retrospective cohort study of women from the National Free Preconception Health Examination Project with singleton birth from 121 counties/districts in 21 cities of Guangdong Province, China, from Jan. 1, 2013, to Dec. 31, 2017. Women were included if their prepregnancy fasting glucose was less than 7.0 mmol/L. The primary outcomes were preterm birth (gestational age <37 weeks), early preterm birth (gestational age <34 weeks), large for gestational age (birthweight by gestational age >90th percentile based on the international standards in the International Fetal and Newborn Growth Consortium for the 21st Century study), and severe large for gestational age (birthweight by gestational age >97th percentile). We calculated the adjusted risk ratio for impaired fasting glucose and a 1 standard deviation increase in fasting glucose.

RESULTS

We included 640,469 women. Of these, 31,006 (4.84%) met the World Health Organization cut point for impaired fasting glucose, 32,640 (5.10%) had preterm birth and 7201 (1.12%) had early preterm birth, 45,532 (7.11%) had large for gestational age birth, and 16,231 (2.53%) had severe large for gestational age birth. Compared with women with normoglycaemia, women with prepregnancy impaired fasting glucose had a 7.0% higher risk of preterm birth (adjusted risk ratio, 1.07, 95% confidence interval, 1.02-1.12), 10.0% had a higher risk of large for gestational age (adjusted risk ratio, 1.10, 95% confidence interval, 1.06-1.14), and 17.0% had a higher risk of severe large for gestational age (adjusted risk ratio, 1.17, 95% confidence interval, 1.10-1.26). No significant association of prepregnancy impaired fasting glucose with early preterm birth was found. The association of prepregnancy impaired fasting glucose with preterm birth and large for gestational age were similar in subgroups of women with various baseline characteristics. Adjusted risk ratio for preterm birth per standard deviation fasting glucose (0.7 mmol/L) was 0.99 (95% confidence interval, 0.98-1.00), for early preterm birth an adjusted risk ratio of 0.99 (confidence interval, 0.97-1.02), for large for gestational age an adjusted risk ratio of 1.04 (confidence interval, 1.03-1.05), and for severe large for gestational age an adjusted risk ratio of 1.03 (confidence interval, 1.01-1.04).

CONCLUSION

Our data suggest that maternal prepregnancy impaired fasting glucose increases the risk of preterm birth, large for gestational age, and severe large for gestational age. Data also suggest that the World Health Organization cut point of impaired fasting glucose is too restrictive, and lower levels of fasting glucose also increase the risk of large for gestational age and severe for severe gestational age in the Chinese population. Further investigation is warranted to determine whether and how counseling and interventions for women with prepregnancy impaired fasting glucose could reduce the risk of preterm birth and large for gestational age.

Persisting inequalities in birth outcomes related to neighbourhood deprivation

INTRODUCTION

Health inequalities can be observed in early life as unfavourable birth outcomes. Evidence indicates that neighbourhood socioeconomic circumstances influence health. However, studies looking into temporal trends in inequalities in birth outcomes including neighbourhood socioeconomic conditions are scarce. The aim of this work was to study how inequalities in three different key birth outcomes have changed over time across different strata of neighbourhood deprivation.

METHODS

Nationwide time trends ecological study with area-level deprivation in quintiles as exposure. The study population consisted of registered singleton births in the Netherlands 2003-2017 between 24 and 41 weeks of gestation. Outcomes used were perinatal mortality, premature birth and small for gestational age (SGA). Absolute rates for all birth outcomes were calculated per deprivation quintile. Time trends in birth outcomes were examined using logistic regression models. To investigate relative inequalities, rate ratios for all outcomes were calculated per deprivation quintile.

RESULTS

The prevalence of all unfavourable birth outcomes decreased over time: from 7.2 to 4.1 per 1000 births for perinatal mortality, from 61.8 to 55.6 for premature birth, and from 121.9 to 109.2 for SGA. Inequalities in all birth outcomes have decreased in absolute terms, and the decline was largest in the most deprived quintile. Time trend analyses confirmed the overall decreasing time trends for all outcomes, which were significantly steeper for the most deprived quintile. In relative terms however, inequalities remained fairly constant.

CONCLUSION

In absolute terms, inequalities in birth outcomes by neighbourhood deprivation in the Netherlands decreased between 2003 and 2017. However, relative inequalities remained persistent.

Preterm births in Iceland 1997-2016: Preterm birth rates by gestational age groups and type of preterm birth

BACKGROUND

The frequency of preterm births has been increasing globally, mainly due to a rise in iatrogenic late preterm births. The aim of this study was to assess the prevalence of preterm births in Iceland during 1997-2016 by type of preterm birth.

METHODS

This study included all live births in Iceland during 1997-2016 identified from the Icelandic Medical Birth Registry. Risk of preterm birth by time period was assessed with Poisson regression models adjusted for demographic variables and indications for iatrogenic births.

RESULTS

The study population included 87 076 infants, of which 4986 (5.7%) were preterm. The preterm birth rate increased from 5.3% to 6.1% (adjusted rate ratio [ARR] = 1.16, confidence interval [CI] = 1.07-1.26) between 1997-2001 and 2012-2016 overall. The increase was only evident in multiples (ARR 1.41, 95% CI 1.21-1.65), not singletons (1.07, 0.97-1.19). The rate of late preterm births (34-36 weeks) increased significantly (1.24, 1.14-1.40), and the rate of iatrogenic preterm births more than doubled during this period even after adjustment for identified medical indications (2.40, 2.00-2.88). The rate of spontaneous preterm births decreased during the study period (0.63, 0.55-0.73), and the rate of PPROM increased (1.31, 1.09-1.57). The most common contributing indications for iatrogenic births were fetal distress (26.2%), hypertensive disorders (18.2%), and severe preeclampsia (16.9%).

CONCLUSIONS

Preterm birth rates increased in multiples in Iceland between 1997 and 2016, and late and iatrogenic preterm births increased overall. The increase in iatrogenic preterm births remained significant after adjusting for medical indications, suggesting that other factors might be affecting the rise.

Development and validation of a simplified score to predict neonatal mortality risk among neonates weighing 2000 g or less (NMR-2000): an analysis using data from the UK and The Gambia

Background

78% of neonatal deaths occur in sub-Saharan Africa and southern Asia, among which, more than 80% are in low birthweight babies. Existing neonatal mortality risk scores have primarily been developed for high-resource settings. The aim of this study was to develop and validate a score that is practicable for low-income and middle-income countries to predict in-hospital mortality among neonates born weighing 2000 g or less using datasets from the UK and The Gambia.

Methods

This analysis used retrospective data held in the UK National Neonatal Research Database from 187 neonatal units, and data from the Edward Francis Small Teaching Hospital (EFSTH), Banjul, The Gambia. In the UK dataset, neonates were excluded if birthweight was more than 2000 g; if the neonate was admitted aged more than 6 h or following discharge; if the neonate was stillborn; if the neonate died in delivery room; or if they were moribund on admission. The Gambian dataset included all neonates weighing less than 2000 g who were admitted between May 1, 2018, and Sept 30, 2019, who were screened for but not enrolled in the Early Kangaroo Mother Care Trial. 18 studies were reviewed to generate a list of 84 potential parameters. We derived a model to score in-hospital neonatal mortality risk using data from 55 029 admissions to a random sample of neonatal units in England and Wales from Jan 1, 2010, to Dec 31, 2016. All candidate variables were included in a complete multivariable model, which was progressively simplified using reverse stepwise selection. We validated the new score (NMR-2000) on 40 329 admissions to the remaining units between the same dates and 14 818 admissions to all units from Jan 1, to Dec 31, 2017. We also validated the score on 550 neonates admitted to the EFSTH in The Gambia.

Findings

18 candidate variables were selected for inclusion in the modelling process. The final model included three parameters: birthweight, admission oxygen saturation, and highest level of respiratory support within 24 h of birth. NMR-2000 had very good discrimination and goodness-of-fit across the UK samples, with a c-index of 0·8859–0·8930 and a Brier score of 0·0232–0·0271. Among Gambian neonates, the model had a c-index of 0·8170 and a Brier score of 0·1688. Predictive ability of the simplified integer score was similar to the model using regression coefficients, with c-indices of 0·8903 in the UK full validation sample and 0·8082 in the Gambian validation sample.

Interpretation

NMR-2000 is a validated mortality risk score for hospitalised neonates weighing 2000 g or less in settings where pulse oximetry is available. The score is accurate and simplified for bedside use. NMR-2000 requires further validation using a larger dataset from low-income and middle-income countries but has the potential to improve individual and population-level neonatal care resource allocation.

Funding

Bill & Melinda Gates Foundation; Eunice Kennedy Shriver National Institute of Child Health & Human Development; Wellcome Trust; and Joint Global Health Trials scheme of Department of Health and Social Care, Department for International Development, Medical Research Council, and Wellcome Trust.

Maternal nutritional status mediates the linkage between household food insecurity and mid-infancy size in rural Bangladesh

Household food insecurity (HFI) is a major concern in South Asia. The pathways by which HFI may reduce child growth remain inadequately understood. In a cohort study of 12 693 maternal-infant dyads in rural Bangladesh, we examined association and likely explanatory pathways linking HFI, assessed using a validated nine-item perception-based index, to infant size at 6 months. Mothers were assessed early in pregnancy for anthropometric status, dietary diversity and socio-economic status. Infants were assessed for weight, length, and arm, chest and head circumferences and breast and complementary feeding status at birth and 6 months of age. Extent of HFI shared a negative, dose-response association with all measures of infant size at 6 months and odds of wasting and stunting; 57-89 % of variances in the unadjusted models were explained by prenatal factors (maternal nutritional status and dietary diversity), and birth size adjusted for gestational age. Postnatal infant breast and complementary feeding and morbidity exposures explained the remaining fraction of the significant association between HFI and differences in infant arm and chest circumferences and odds of underweight. Contextual (i.e. socio-economic) factors finally brought remaining non-significant fractions of the food insecurity-related mid-infancy growth deficit to practically zero. Improving food security prior to pregnancy and during gestation would likely improve infant growth the most in rural Bangladesh.

Management of Respiratory Distress Syndrome in Preterm Infants In Wales: A Full Audit Cycle of a Quality Improvement Project

Respiratory Distress Syndrome (RDS) is the commonest diagnosis after premature birth. We aimed to audit clinical practices before and after introduction of a national guideline in Wales on RDS management. Anonymised, prospective data on all infants born at <34 weeks of gestation and cared for at one of the participating neonatal units in Wales were collected in two six-month time periods in 2015 and 2018. A national guideline was introduced in 2016 by the Wales Neonatal Network. Data collection included areas of antenatal management, delivery room stabilisation, invasive and non-invasive respiratory support, surfactant treatment and elements of supportive care. Univariate and multivariate methods were used to compare data between the two epochs. Comparing care before and after introduction of the national guideline, areas of significant improvement include use of targeted tidal volume ventilation, use of caffeine therapy, oxygen therapy post-surfactant and increasing early use of parenteral nutrition. Areas of poorer management included levels of positive end expiratory pressures and timing of introduction of enteral feeds. Little variation was seen between level two and three units, although gestational age was a significant independent variable for several practices, including delayed cord clamping, stabilisation with intubation, early enteral feeding and caffeine administration. A national guideline for management of RDS in Wales has significantly improved practice in several areas. However, despite a large volume of high-quality evidence and robust guidance, there remains a significant variation in some elements of best practice for RDS management. Further work should focus on education and training, especially for elements requiring cross-departmental work.

Chained Risk Assessment for Life-Long Disease Burden of Early Exposures - Demonstration of Concept Using Prenatal Maternal Smoking

Traditional risk factors and environmental exposures only explain less than half of the disease burden. The developmental origin of the health and disease (DOHaD) concept proposes that prenatal and early postnatal exposures increase disease susceptibility throughout life. The aim of this work is to demonstrate the application of the DOHaD concept in a chained risk assessment and to provide an estimate of later in life burden of disease related to maternal smoking. We conducted three systematic literature searches for meta-analysis and reviewed the literature reporting meta-analyses of long-term health outcomes associated with maternal smoking and intermediate risk factors (preterm birth, low birth weight, childhood overweight). In the chained model the three selected risk factors explained an additional 2% (34,000 DALY) of the total non-communicable disease burden (1.4 million DALY) in 2017. Being overweight in childhood was the most important risk factor (28,000 DALY). Maternal smoking was directly associated with 170 DALY and indirectly via the three intermediate risk factors 1000 DALY (1200 DALY in total). The results confirm the potential to explain a previously unattributed part of the non-communicable diseases by the DOHAD concept. It is likely that relevant outcomes are missing, resulting in an underestimation of disease burden.

Risk of preterm birth after prior term cesarean

Objective

To determine the risk of overall preterm birth (PTB) and spontaneous PTB in a pregnancy after a caesarean section (CS) at term.

Design

Longitudinal linked national cohort study.

Setting

The Dutch Perinatal Registry (1999–2009).

Population

268 495 women with two subsequent singleton pregnancies were identified.

Methods

A cohort study based on linked registered data from two subsequent pregnancies in the Netherlands.

Main outcome measures

The incidence of overall PTB and spontaneous PTB with subgroup analysis on gestational age at first delivery and type of CS (planned or unplanned).

Results

Of 268 495 women with a singleton first pregnancy who delivered at term, 15.76% (n = 42 328) had a CS. The incidence of PTB in the second pregnancy was 2.79% (n = 1182) in women with a previous CS versus 2.46% (n = 5570) in women with a previous vaginal delivery (adjusted odds ratio [aOR] 1.14, 95% confidence interval [CI] 1.07–1.21). This increased risk is mainly driven by an increased risk of spontaneous PTB after previous CS at term (aOR 1.50, 95% CI 1.38–1.70). Analysis for type of CS compared with vaginal delivery showed an aOR on spontaneous PTB of 1.86 (95% CI 1.58–2.18) for planned CS and an aOR of 1.40 (95% CI 1.24–1.58) for unplanned CS.

Conclusions

CS at term is associated with a marginally increased risk of spontaneous PTB in a subsequent pregnancy.

Tweetable abstract

Caesarean section at term is associated with a marginally increased risk of spontaneous PTB in a subsequent pregnancy.

Caesarean section at term is associated with a marginally increased risk of spontaneous PTB in a subsequent pregnancy.

Factors Associated with Preterm Birth and Low Birth Weight in Abu Dhabi, the United Arab Emirates

Both preterm birth and low birth weight (LBW) represent major public health problems worldwide due to their association with the catastrophic effects of morbidity and mortality. Few data exist about such adverse pregnancy outcomes. The current study aimed to investigate the prevalence of and factors associated with preterm birth and LBW among mothers of children under two years in Abu Dhabi, United Arab Emirates. Data were collected in clinical and non-clinical settings across various geographical areas in Abu Dhabi. The data were analyzed using both descriptive and inferential statistics. A total of 1610 mother–child pairs were included in the current study. Preterm birth rate was 102 (6.3%) with a 95% confidence interval [CI] (6.1%, 6.5%) and the LBW rate was 151 (9.4%) with a 95% CI (9.3%, 9.5%). The mean (SD) of gestational age (GA) and birth weight at delivery was 39.1 (1.9) weeks and 3080.3 (518.6) grams, respectively. Factors that were positively associated with preterm birth were Arab mothers, maternal education level below secondary, caesarean section, and LBW. LBW was associated with female children, caesarean section (CS), first child order, and preterm birth. The current study highlighted the need for further interventional research to tackle these public health issues such as reducing the high CS rate and improving maternal education.

Understanding how maternal social and biological factors are related to fetal growth in an urban South African cohort

The aim of this study was to identify social and biological drivers of fetal growth by examining associations with household, preconception, and pregnancy factors in a cohort from Soweto, South Africa. Complete data and ultrasound scans were collected on 519 women between 2013 and 2016 at 6 time points during pregnancy (<14, 14-18, 19-23, 24-28, 29-33 weeks, and 34-38 weeks). Household-level factors, preconception health, baseline body mass index (BMI), and demographic data were collected at the first visit. During pregnancy, gestational weight gain (GWG; kg/week) was calculated. At 24-28 weeks of gestation, oral glucose tolerance test was used to determine gestational diabetes mellitus (GDM) status, and hypertension status was characterised. Longitudinal growth in head circumference, abdominal circumference, biparietal diameter, and femur length were modelled using the Superimposition by Translation and Rotation, a shape-invariant model which produces growth curves against gestational age. A priori identified exposure variables were then included in a series of sex-stratified hierarchical regression models for each fetal growth outcome. No household-level factors were associated with fetal growth. Maternal BMI at baseline was positively associated with all outcome parameters in males and females. Both GWG (in males and females) and GDM (in males) were significant positive predictors of abdominal growth. Males showed more responsiveness to abdominal growth, while females were more responsive to linear growth. Thus, fetal growth was largely predicted by maternal biological factors, and sexual dimorphism in the responsiveness of fetal biometry to biological exposures was evident.

Associations of maternal ambient temperature exposures during pregnancy with the risk of preterm birth and the effect modification of birth order during the new baby boom: A birth cohort study in Guangzhou, China

Maternal exposures to ambient temperatures during pregnancy may increase the preterm birth (PTB) risk; however, which periods have stronger effects remain controversial. The effects of temperature exposure on PTB in first- and second-born neonate groups may be different during the new baby boom that has followed the Two-child Policy in China. We examined a birth cohort of 4928 pregnant women beginning in 2016 in Guangzhou, China. An inverse distance weighted method was used to estimate the temperature exposure at each individual residential address. A distribution lag non-linear model incorporating a Cox proportional hazard model was employed to estimate the effects of temperature exposure on PTB and test the effects modification of birth order related to the new baby boom. A total of 4101 pregnant women were included, of which 234 (5.7%) experienced PTB. Compared with the mean temperature (23.0 °C), we found a significantly higher risks of PTB associated with high temperatures (i.e, 30 °C [95th centile]) from the 4th to 8th, and 22nd to 27th gestational weeks. A peak effect was found during the 6th week (HR = 1.79, 95% CI: 1.26, 2.54) and 24th week (HR = 1.83, 95% CI: 1.27, 2.62). The risks of PTB were reduced for low temperatures (i.e. 14 °C [5th centile] versus 23.0 °C) from the 2nd to 10th and 20th to 26th gestational weeks, and the negative peak effect was found during the 4th week (HR = 0.43, 95% CI: 0.26, 0.72) and 23rd week (HR = 0.59, 95% CI: 0.43, 0.83). Stratification analyses showed that significant effects of 30 °C versus 23 °C on PTB were observed during the 4th to 8th weeks in the second-born neonate, and the peak effect was found in the 6th week (HR = 2.13, 95% CI: 1.31, 3.47). However, we did not find significant effects of 30 °C during the same weeks in the first-born neonate group. Maternal exposures to higher temperatures during pregnancy may increase the risk of PTB, and lower temperatures may decrease the risk of PTB. Stronger effects of temperature exposures during the first trimester on PTB risk were found among the second-born neonates than among the first-born neonates.

An effectiveness-implementation hybrid type 1 trial assessing the impact of group versus individual antenatal care on maternal and infant outcomes in Malawi

BACKGROUND

Sub-Saharan Africa has the world's highest rates of maternal and perinatal mortality and accounts for two-thirds of new HIV infections and 25% of preterm births. Antenatal care, as the entry point into the health system for many women, offers an opportunity to provide life-saving monitoring, health promotion, and health system linkages. Change is urgently needed, because potential benefits of antenatal care are not realized when pregnant women experience long wait times and short visits with inconsistent provisioning of essential services and minimal health promotion, especially for HIV prevention. This study answers WHO's call for the rigorous study of group antenatal care as a transformative model that provides a positive pregnancy experience and improves outcomes.

METHODS

Using a hybrid type 1 effectiveness-implementation design, we test the effectiveness of group antenatal care by comparing it to individual care across 6 clinics in Blantyre District, Malawi. Our first aim is to evaluate the effectiveness of group antenatal care through 6 months postpartum. We hypothesize that women in group care and their infants will have less morbidity and mortality and more positive HIV prevention outcomes. We will test hypotheses using multi-level hierarchical models using data from repeated surveys (four time points) and health records. Guided by the consolidated framework for implementation research, our second aim is to identify contextual factors related to clinic-level degree of implementation success. Analyses use within and across-case matrices.

DISCUSSION

This high-impact study addresses three global health priorities, including maternal and infant mortality, HIV prevention, and improved quality of antenatal care. Results will provide rigorous evidence documenting the effectiveness and scalability of group antenatal care. If results are negative, governments will avoid spending on less effective care. If our study shows positive health impacts in Malawi, the results will provide strong evidence and valuable lessons learned for widespread scale-up in other low-resource settings. Positive maternal, neonatal, and HIV-related outcomes will save lives, impact the quality of antenatal care, and influence health policy as governments make decisions about whether to adopt this innovative healthcare model.

TRIAL REGISTRATION

ClinicalTrials.gov registration number NCT03673709. Registered on September 17, 2018.

Altered Cortical Gyrification in Adults Who Were Born Very Preterm and Its Associations With Cognition and Mental Health

BACKGROUND

The last trimester of pregnancy is a critical period for the establishment of cortical gyrification, and altered folding patterns have been reported following very preterm birth (< 33 weeks of gestation) in childhood and adolescence. However, research is scant on the persistence of such alterations in adulthood and their associations with cognitive and psychiatric outcomes.

METHODS

We studied 79 very preterm and 81 age-matched full-term control adults. T1-weighted magnetic resonance images were used to measure a local gyrification index (LGI), indicating the degree of folding across multiple vertices of the reconstructed cortical surface. Group and group-by-sex LGI differences were assessed by means of per-vertex adjustment for cortical thickness and overall intracranial volume. Within-group correlations were also computed between LGI and functional outcomes, including general intelligence (IQ) and psychopathology.

RESULTS

Very preterm adults had significantly reduced LGI in extensive cortical regions encompassing the frontal, anterior temporal, and occipitoparietal lobes. Alterations in lateral fronto-temporal-parietal and medial occipitoparietal regions were present in both men and women, although men showed more extensive alterations. In both very preterm and control adults, higher LGI was associated with higher IQ and lower psychopathology scores, with the spatial distribution of these associations substantially differing between the two groups.

CONCLUSIONS

Very preterm adults' brains are characterized by significant and widespread local hypogyria, and these alterations might be implicated in cognitive and psychiatric outcomes. Gyrification reflects an early developmental process and provides a fingerprint for very preterm birth.

Birth Weight and Cardiorespiratory Fitness Among Young Men Born at Term: The Role of Genetic and Environmental Factors

Background Preterm delivery and low birth weight are prospectively associated with low cardiorespiratory fitness (CRF). However, whether birth weight, within the at-term range, is associated with later CRF is largely unknown. Thus, the aim of the current study was to examine this issue and whether such association, if any, is explained by shared and/or nonshared familial factors. Methods and Results We conducted a prospective cohort study, including 286 761 young male adults and a subset of 52 544 siblings born at-term. Objectively measured data were retrieved from total population registers. CRF was tested at conscription and defined as the maximal load obtained on a cycle ergometer. We used linear and nonlinear and fixed-effects regression analyses to explore associations between birth weight and CRF. Higher birth weight, within the at-term range, was strongly associated with increasing CRF in a linear fashion. Each SD increase in birth weight was associated with an increase of 7.9 (95% CI, 7.8-8.1) and 6.6 (95% CI; 5.9-7.3) Wmax in the total and sibling cohorts, respectively. The association did not vary with young adulthood body mass index. Conclusions Birth weight is strongly associated with increasing CRF in young adulthood among men born at-term, across all categories of body mass index. This association appears to be mainly driven by factors that are not shared between siblings. Hence, CRF may to some extent be determined already in utero. Prevention of low birth weight, also within the at-term-range, can be a feasible mean of increasing adult CRF and health.

Small for gestational age birth may increase airflow limitation in bronchopulmonary dysplasia

OBJECTIVES

To determine significant indices for assessing the pulmonary function of infants according to bronchopulmonary dysplasia (BPD) severity and to evaluate whether small for gestational age (SGA) could affect pulmonary function in BPD.

METHODS

We evaluated 117 preterm infants who had undergone tidal breathing flow-volume loop and multiple-breath washout analyses within 7 months after birth. We categorized preterm infants according to BPD severity into mild/moderate BPD (n = 86), severe BPD (n = 21), and without BPD (n = 10) and the presence of SGA or appropriate gestational age (AGA) using the Fenton growth chart. We evaluated nine healthy term infants as controls.

RESULTS

The tidal breathing ratio (time to peak expiratory flow/expiratory time [t_PEF /t_E ]) was significantly lower in infants with severe BPD than in those with mild/moderate BPD. Lung clearance index (LCI) was not different based on BPD severity. In the correlation analysis after adjusting for gestational age and sex, t_PEF /t_E was correlated with the duration of mechanical ventilation (r = -0.347, P < .001) and the duration of oxygen supply (r = -0.248, P = .013) in infants with BPD. The proportion of "lower t_PEF /t_E ," defined as below the cut-off value, was greater in SGA infants (P = .017), while no significant difference was seen in the percentage of "higher LCI," defined as above the cut-off value between SGA and AGA infants.

CONCLUSIONS

In infants with BPD, t_PEF /t_E could be a useful pulmonary index which shows lower values in severe BPD. The finding of SGA in infants with BPD could be associated with poor pulmonary function related to the t_PEF /t_E values.

Association of antepartum depression, generalized anxiety, and posttraumatic stress disorder with infant birth weight and gestational age at delivery

BACKGROUND

Low- and middle-income countries bear a disproportionate burden of preterm birth (PTB) and low infant birth weight (LBW) complications where affective and anxiety disorders are more common in the antepartum period than in industrialized countries.

OBJECTIVE

To evaluate the extent to which early pregnancy antepartum depression, generalized anxiety disorder, and posttraumatic stress disorder (PTSD) are associated with infant birth weight and gestational age at delivery among a cohort of pregnant women in Peru.

METHODS

Our prospective cohort study consisted of 4408 pregnant women. Antepartum depression, generalized anxiety, and PTSD were assessed in early pregnancy using the Patient Health Questionnaire-9, Generalized Anxiety Disorder Scale-7 and PTSD Checklist - Civilian Version, respectively. Pregnancy outcome data were obtained from medical records. Multivariable linear and logistic regression procedures were used to estimate adjusted measures of association (β coefficients and odds ratios) and 95% confidence intervals (CI).

RESULTS

After adjusting for confounders, women with antepartum generalized anxiety (32.6% prevalence) had higher odds of LBW (adjusted odds ratio (OR)=1.47; 95%CI: 1.10-1.95) and were more likely to deliver small for gestational age (OR = 1.39; 95%CI: 1.01-1.92) infants compared to those without anxiety. Compared to those without PTSD, women with PTSD (34.5%) had higher odds of delivering preterm (OR = 1.28; 95%CI: 1.00-1.65) yet PTSD was not associated with LBW nor gestational age at delivery. Women with antepartum depression (26.2%) were at no increased risk of delivering a preterm, low-birth-weight or small-for-gestational-age infant.

LIMITATIONS

Our ability to make casual inferences from this observational study is limited; however, these findings are consistent with prior studies.

CONCLUSION

Generalized anxiety disorder during pregnancy appeared to increase odds of delivering a low-birth-weight or small-for-gestational-age infant, while PTSD was associated with increased odds of delivering preterm. Our findings, and those of others, suggest antenatal care should be tailored to screen for and provide additional mental health services to patients.

Operationalising kangaroo Mother care before stabilisation amongst low birth Weight Neonates in Africa (OMWaNA): protocol for a randomised controlled trial to examine mortality impact in Uganda

Background

There are 2.5 million neonatal deaths each year; the majority occur within 48 h of birth, before stabilisation. Evidence from 11 trials shows that kangaroo mother care (KMC) significantly reduces mortality in stabilised neonates; however, data on its effect among neonates before stabilisation are lacking. The OMWaNA trial aims to determine the effect of initiating KMC before stabilisation on mortality within seven days relative to standard care. Secondary objectives include exploring pathways for the intervention’s effects and assessing incremental costs and cost-effectiveness between arms.

Methods

We will conduct a four-centre, open-label, individually randomised, superiority trial in Uganda with two parallel groups: an intervention arm allocated to receive KMC and a control arm receiving standard care. We will enrol 2188 neonates (1094 per arm) for whom the indication for KMC is ‘uncertain’, defined as receiving ≥ 1 therapy (e.g. oxygen). Admitted singleton, twin and triplet neonates (triplet if demise before admission of ≥ 1 baby) weighing ≥ 700–≤ 2000 g and aged ≥ 1–< 48 h are eligible. Treatment allocation is random in a 1:1 ratio between groups, stratified by weight and recruitment site. The primary outcome is mortality within seven days. Secondary outcomes include mortality within 28 days, hypothermia prevalence at 24 h, time from randomisation to stabilisation or death, admission duration, time from randomisation to exclusive breastmilk feeding, readmission frequency, daily weight gain, infant–caregiver attachment and women’s wellbeing at 28 days. Primary analyses will be by intention-to-treat. Quantitative and qualitative data will be integrated in a process evaluation. Cost data will be collected and used in economic modelling.

Discussion

The OMWaNA trial aims to assess the effectiveness of KMC in reducing mortality among neonates before stabilisation, a vulnerable population for whom its benefits are uncertain. The trial will improve understanding of pathways underlying the intervention’s effects and will be among the first to rigorously compare the incremental cost and cost-effectiveness of KMC relative to standard care. The findings are expected to have broad applicability to hospitals in sub-Saharan Africa and southern Asia, where three-quarters of global newborn deaths occur, as well as important policy and programme implications.

Trial registration

ClinicalTrials.gov, NCT02811432. Registered on 23 June 2016.

Adverse birth outcomes and their clinical phenotypes in an urban Zambian cohort

Background: Few cohort studies of pregnancy in sub-Saharan Africa use rigorous gestational age dating and clinical phenotyping. As a result, incidence and risk factors of adverse birth outcomes are inadequately characterized. Methods: The Zambian Preterm Birth Prevention Study (ZAPPS) is a prospective observational cohort established to investigate adverse birth outcomes at a referral hospital in urban Lusaka. This report describes ZAPPS phase I, enrolled August 2015 to September 2017. Women were followed through pregnancy and 42 days postpartum. At delivery, study staff assessed neonatal vital status, birthweight, and sex, and assigned a delivery phenotype. Primary outcomes were: (1) preterm birth (PTB; delivery <37 weeks), (2) small-for-gestational-age (SGA; <10 ^th percentile weight-for-age at birth), and (3) stillbirth (SB; delivery of an infant without signs of life). Results: ZAPPS phase I enrolled 1450 women with median age 27 years (IQR 23-32). Most participants (68%) were multiparous, of whom 41% reported a prior PTB and 14% reported a prior stillbirth. Twins were present in 3% of pregnancies, 3% of women had short cervix (<25mm), 24% of women were HIV seropositive, and 5% were syphilis seropositive. Of 1216 (84%) retained at delivery, 15% were preterm, 18% small-for-gestational-age, and 4% stillborn. PTB risk was higher with prior PTB (aRR 1.88; 95%CI 1.32-2.68), short cervix (aRR 2.62; 95%CI 1.68-4.09), twins (aRR 5.22; 95%CI 3.67-7.43), and antenatal hypertension (aRR 2.04; 95%CI 1.43-2.91). SGA risk was higher with twins (aRR 2.75; 95%CI 1.81-4.18) and antenatal hypertension (aRR 1.62; 95%CI 1.16-2.26). SB risk was higher with short cervix (aRR 6.42; 95%CI 2.56-16.1). Conclusio ns: This study confirms high rates of PTB, SGA, and SB among pregnant women in Lusaka, Zambia. Accurate gestational age dating and careful ascertainment of delivery data are critical to understanding the scope of adverse birth outcomes in low-resource settings.

Adverse birth outcomes and their clinical phenotypes in an urban Zambian cohort

Background: Few cohort studies of pregnancy in sub-Saharan Africa use rigorous gestational age dating and clinical phenotyping. As a result, incidence and risk factors of adverse birth outcomes are inadequately characterized. Methods: The Zambian Preterm Birth Prevention Study (ZAPPS) is a prospective observational cohort established to investigate adverse birth outcomes at a referral hospital in urban Lusaka. This report describes ZAPPS phase I, enrolled August 2015 to September 2017. Women were followed through pregnancy and 42 days postpartum. At delivery, study staff assessed neonatal vital status, birthweight, and sex, and assigned a delivery phenotype. Primary outcomes were: (1) preterm birth (PTB; delivery <37 weeks), (2) small-for-gestational-age (SGA; <10 ^th percentile weight-for-age at birth), and (3) stillbirth (SB; delivery of an infant without signs of life). Results: ZAPPS phase I enrolled 1450 women with median age 27 years (IQR 23-32). Most participants (68%) were multiparous, of whom 41% reported a prior PTB and 14% reported a prior stillbirth. Twins were present in 3% of pregnancies, 3% of women had short cervix (<25mm), 24% of women were HIV seropositive, and 5% were syphilis seropositive. Of 1216 (84%) retained at delivery, 15% were preterm, 18% small-for-gestational-age, and 4% stillborn. PTB risk was higher with prior PTB (aRR 1.88; 95%CI 1.32-2.68), short cervix (aRR 2.62; 95%CI 1.68-4.09), twins (aRR 5.22; 95%CI 3.67-7.43), and antenatal hypertension (aRR 2.04; 95%CI 1.43-2.91). SGA risk was higher with twins (aRR 2.75; 95%CI 1.81-4.18) and antenatal hypertension (aRR 1.62; 95%CI 1.16-2.26). SB risk was higher with short cervix (aRR 6.42; 95%CI 2.56-16.1). Conclusio ns: This study confirms high rates of PTB, SGA, and SB among pregnant women in Lusaka, Zambia. Accurate gestational age dating and careful ascertainment of delivery data are critical to understanding the scope of adverse birth outcomes in low-resource settings.

Intimate partner violence and perinatal health: a systematic review

BACKGROUND

Physical, psychological and sexual intimate partner violence (IPV) has been described in the literature as different types of IPV experienced by women during pregnancy all over the world.

OBJECTIVES

To review and summarise systematically the empirical evidence on the links between IPV during pregnancy and the perinatal health of mothers and fetuses/neonates.

SEARCH STRATEGY

MEDLINE (Ovid), CINAHL, Embase, Nursing@ovid (Ovid) and LILACS were searched (2008-2018).

SELECTION CRITERIA

Observational studies that examined perinatal health outcomes (i.e. pre-term birth, low birthweight, miscarriage, perinatal death and premature rupture of membranes) in pregnant women exposed to IPV.

DATA COLLECTION AND ANALYSIS

Information on study characteristics, type of IPV measured, study design, methodological quality and outcome variable extracted.

RESULTS

Fifty studies were included. Twenty-nine analysed undifferentiated IPV (n = 25 489), 34 included physical IPV (n = 7333), 22 analysed psychological IPV (n = 7833) and 18 examined sexual IPV (n = 2388). Fifteen studies were from Asia, 12 from North America and Oceania, and 12 from Central and South America. The studies examined the association between IPV and 39 different perinatal health outcomes. The most frequent outcomes reported were pre-term birth (50%), low birthweight (46%), miscarriage (30%), perinatal death (20%) and premature rupture of membranes (20%). A significant association with perinatal health outcomes was reported by 12 of the studies analysing undifferentiated IPV, 18 physical IPV, six psychological IPV and two sexual IPV.

CONCLUSIONS

The relation between IPV and perinatal health outcomes can be seen in different epidemiological designs and countries. In all, 39 different outcomes were identified and 29 were associated with IPV.

TWEETABLE ABSTRACT

A variety of poor perinatal health outcomes are associated with psychological, physical and sexual IPV.

Preterm birth prediction in asymptomatic women at mid-gestation using a panel of novel protein biomarkers: the Prediction of PreTerm Labor (PPeTaL) study

BACKGROUND

Accurate prediction of spontaneous preterm labor/preterm birth in asymptomatic women remains an elusive clinical challenge because of the multi-etiological nature of preterm birth.

OBJECTIVE

The aim of this study was to develop and validate an immunoassay-based, multi-biomarker test to predict spontaneous preterm birth.

MATERIALS AND METHODS

This was an observational cohort study of women delivering from December 2017 to February 2019 at 2 maternity hospitals in Melbourne, Australia. Cervicovaginal fluid samples were collected from asymptomatic women at gestational week 16⁺⁰-24⁺⁰, and biomarker concentrations were quantified by enzyme-linked immunosorbent assay. Women were assigned to a training cohort (n = 136) and a validation cohort (n = 150) based on chronological delivery dates.

RESULTS

Seven candidate biomarkers representing key pathways in utero-cervical remodeling were discovered by high-throughput bioinformatic search, and their significance in both in vivo and in vitro studies was assessed. Using a combination of the biomarkers for the first 136 women allocated to the training cohort, we developed an algorithm to stratify term birth (n = 124) and spontaneous preterm birth (n = 12) samples with a sensitivity of 100% (95% confidence interval, 76-100%) and a specificity of 74% (95% confidence interval, 66-81%). The algorithm was further validated in a subsequent cohort of 150 women (n = 139 term birth and n = 11 preterm birth), achieving a sensitivity of 91% (95% confidence interval, 62-100%) and a specificity of 78% (95% confidence interval, 70-84%).

CONCLUSION

We have identified a panel of biomarkers that yield clinically useful diagnostic values when combined in a multiplex algorithm. The early identification of asymptomatic women at risk for preterm birth would allow women to be triaged to specialist clinics for further assessment and appropriate preventive treatment.

Respiratory syncytial virus acute respiratory infection-associated hospitalizations in preterm Mexican infants: A cohort study

Background

Respiratory syncytial virus (RSV) is the leading cause of severe acute respiratory infections (ARI) in preterm infants. The incidence of RSV‐associated hospitalizations has not been defined in Mexico.

Objectives

To determine the incidence of ARI‐ and RSV‐associated hospitalizations in preterm infants during the first year of life.

Methods

Prospective cohort study of 294 preterm infants followed up through monthly telephone calls and routine outpatient visits. Hospitalized children were identified through daily visits to pediatric wards of participating hospitals and through telephone calls. Respiratory samples were tested for RSV by RT‐PCR.

Results

Mean gestational age of participating infants was 33 weeks. Ninety‐six infants were diagnosed with bronchopulmonary dysplasia (BPD) and 17 with congenital heart disease (CHD); 11 had both conditions. There were 71 hospitalization episodes in 53 infants. Respiratory samples for RSV detection were available in 44 hospitalization episodes, and the result was positive in 16 (36.3%). At least one hospitalization for ARI was recorded in 33 of 96 participants with BPD, in seven of 17 with CHD, and 18 of 192 infants without these diagnoses. Five (71.4%) of CHD infants who required admission also had BPD. RSV‐confirmed hospitalization rates were 9.4%, 5.9%, and 2.6% for infants with BPD, CHD, and otherwise healthy preterm infants, respectively. Attributable RSV admission frequencies were estimated to be 13.6%, 16.5%, and 4.1%, respectively.

Conclusions

Mexican preterm infants, particularly those with BPD, have high rates of ARI‐ and RSVassociated hospitalizations. Specific interventions to reduce the incidence of severe infections in this highrisk group are required.

Determinants of Preterm Birth among Women Who Gave Birth in Amhara Region Referral Hospitals, Northern Ethiopia, 2018: Institutional Based Case Control Study

Background

Preterm birth refers to a birth of a baby before 37 completed weeks of gestation and after fetal viability. It is now the leading cause of new born deaths. Although identifying its common risk factors is mandatory to decrease preterm birth and thereby neonatal deaths, there was a dearth of studies in the study area.

Objective

The aim of this study was to identify determinants of preterm birth among women who gave birth in Amhara region referral hospitals, Northwest Ethiopia, 2018.

Method

An institutional based case-control study was conducted from September 01 to December 01/2018. A total of 405 mothers (135 cases and 270 controls) were included in the study. Multistage sampling technique was employed. Data were collected using structured questionnaire through face to face interview and checklist via Chart review. Data were entered into Epi Info version 7 and export to Statistical Package for Social Sciences (SPSS) version 20 for analysis. Descriptive statics like mean, frequency and percentage was used to describe the characteristics of participants. Both bivariable and multivariable analyses were carried out. Variable having  p-value <0.05 in binary logistic regression were the candidate for multivariable analyses. Finally, the statistical significance of the study was claimed based on the Adjusted Odds Ratio (AOR) with 95% Confidence Interval (CI) and its p-value <0.05.

Result

The result of multivariable analysis show that mothers with no formal education (AOR = 2.24; 95% CI: 1.28, 3.91), history of abortion (AOR = 2.92; 95% CI: 1.3, 6.4), multiple gestation (AOR = 4.1; 95% CI: 1.7, 9.8), hemoglobin level <11 gm/dl (AOR = 2.75; 95% CI: 1.11, 7.31), premature rupture of membrane (AOR = 6.4; 95% CI: 3.23, 12.7) and pregnancy induced hypertension (AOR = 4.74; 95% CI: 2.49, 9.0) had statistically significant association with experiencing preterm birth.

Conclusion and Recommendation

Most of the determinants of preterm birth found to be modifiable. Thus, putting emphasis for prevention of obstetric and gynecologic complications such as anemia, premature rupture of membrane and abortion would decrease the incidence of preterm birth. Moreover, strengthening Information Communication Education about prevention of preterm birth was recommended.

Does preterm birth affect child temperament? A meta-analytic study

The present meta-analytic study was conducted to examine differences in temperament between preterm and full-term children, considering behavior style and psychobiological approaches. Moreover, we explored the potential moderators of the associations between prematurity and temperament. A systematic literature search was performed on PubMed, Scopus, Web of Science, and CINAHL. Twenty-two studies were analyzed. Preterm children showed a higher Activity level as well as lower Attentional Focusing and Attention Span/Persistence, in comparison with their full-term counterparts. Extremely preterm children showed a higher Activity level than other preterm levels. These findings support the conclusion that preterm children present with a less regulated temperament relative to those born full term.

HSP70: an alarmin that does not induce high rates of preterm birth but does cause adverse neonatal outcomes

Objective: Preterm labor and birth are strongly associated with sterile intra-amniotic inflammation, a clinical condition that is proposed to be initiated by danger signals, or alarmins. The aim of this study was to investigate whether the intra-amniotic administration of the alarmin heat shock protein 70 (HSP70) induces preterm labor/birth and adverse neonatal outcomes.Methods: Pregnant mice received an intra-amniotic injection of 200 ng (n = 8), 400 ng (n = 6), 500 ng (n = 10), or 1 µg of HSP70 (n = 6). Control mice were injected with saline (n = 10). Following injection, the rates of preterm labor/birth and neonatal mortality were recorded. Neonatal weights at weeks 1, 2, and 3 were also recorded.Results: The intra-amniotic injection of 400 ng [late preterm birth 16.7 ± 16.7% (1/6)], 500 ng [early and late preterm birth 10 ± 10% (1/10) each], or 1 µg [early preterm birth 16.7 ± 16.7% (1/6)] of HSP70 induced low rates of preterm/birth. However, the intra-amniotic injection of 500 ng or 1 µg of HSP70 induced significantly higher rates of neonatal mortality compared to controls [saline 14.2% (10/74), 200 ng 9.8% (6/61), 400 ng 17.9% (9/45), 500 ng 28.8% (23/78), and 1 µg 21.4% (13/49)]. Neonates born to dams injected with 200, 500 ng, or 1 µg HSP70 were leaner than controls (p ≤ .05).Conclusion: Intra-amniotic administration of the alarmin HSP70 did not induce high rates of preterm labor/birth; yet, it did indeed result in adverse neonatal outcomes.

Independent and Combined Effects of Heatwaves and PM2.5 on Preterm Birth in Guangzhou, China: A Survival Analysis

BACKGROUND

Both extreme heat and air pollution exposure during pregnancy have been associated with preterm birth; however, their combined effects are unclear.

OBJECTIVES

Our goal was to estimate the independent and joint effects of heatwaves and fine particulate matter [PM <2.5μm in aerodynamic diameter (PM2.5)], exposure during the final gestational week on preterm birth.

METHODS

Using birth registry data from Guangzhou, China, we included 215,059 singleton live births in the warm season (1 May-31 October) between January 2015 and July 2017. Daily meteorological variables from 5 monitoring stations and PM2.5 concentrations from 11 sites were used to estimate district-specific exposures. A series of cut off temperature thresholds and durations (2, 3, and 4 consecutive d) were used to define 15 different heatwaves. Cox proportional hazard models were used to estimate the effects of heatwaves and PM2.5 exposures during the final week on preterm birth, and departures from additive joint effects were assessed using the relative excess risk due to interaction (RERI).

RESULTS

Numbers of preterm births increased in association with heatwave exposures during the final gestational week. Depending on the heatwave definition used, hazard ratios (HRs) ranged from 1.10 (95% CI: 1.01, 1.20) to 1.92 (1.39, 2.64). Associations were stronger for more intense heatwaves. Combined effects of PM2.5 exposures and heatwaves appeared to be synergistic (RERIs>0) for less extreme heatwaves (i.e., shorter or with relatively low temperature thresholds) but were less than additive (RERIs<0) for more intense heatwaves.

CONCLUSIONS

Our research strengthens the evidence that exposure to heatwaves during the final gestational week can independently trigger preterm birth. Moderate heatwaves may also act synergistically with PM2.5 exposure to increase risk of preterm birth, which adds new evidence to the current understanding of combined effects of air pollution and meteorological variables on adverse birth outcomes. https://doi.org/10.1289/EHP5117.

Management of Oral Feeding Challenges in Neonatal Intensive Care Units (NICUs): A National Survey in China

Objectives: To investigate the current practices of oral feeding difficulties facing high-risk infants in Chinese NICUs. Methods: A questionnaire to survey infant oral feeding practices was distributed to 100 level II and III Chinese neonatal intensive care units (NICUs). Results: Responses were obtained from 88 NICUs. No Units had any structured guidelines regarding the management of infant oral feeding as they transitioned from tube to independent oral feeding. In 54 (61.4%) NICUs, nurses and physicians made shared decisions on when oral feeding were to be initiated. Fifty-four (61.4%) and 22 (25.0%) NICUs used postmenstrual age (PMA) or weight at PMA as a criterion for initiating oral feedings, respectively. The top three criteria to determine introduction of oral feeding were severity of disease, presence of sucking reflex, and trial feeding success. Adverse events were used by 78 Units as indices of oral feeding difficulty. Twenty (22.7%) and 25 (28.4%) Units had access to occupational therapists or nurses who provided oral motor interventions during feeding, i.e., oral support (chin and cheek support, aid to deglutition), non-nutritive sucking with pacifier, and oral stimulation. Conclusions: The management of oral feeding issues in NICUs vary widely in China in relation to the assessment of readiness to oral feeding, daily oral feeding practices and interventions used by staff. It is proposed that an educational program focused on the physiology of infant oral feeding, available evidence-based tools and interventions would assist NICU caregivers develop structured guidelines to improve infants' safe and efficient attainment of independent oral feeding.

The role of maternal infection in preterm birth: evidence from the Brazilian Multicentre Study on Preterm Birth (EMIP)

OBJECTIVES

Evidence suggests that infection or inflammation is a major contributor to early spontaneous preterm birth (sPTB). Therefore, this study aimed to investigate the development and causes of maternal infection associated with maternal and neonatal outcomes in women with sPTB.

METHODS

This was a secondary analysis of a multicenter cross-sectional study with a nested case-control component, the Brazilian Multicentre Study on Preterm Birth (EMIP), conducted from April 2011 to July 2012 in 20 Brazilian referral obstetric hospitals. Women with preterm birth (PTB) and their neonates were enrolled. In this analysis, 2,682 women undergoing spontaneous preterm labor and premature pre-labor rupture of membranes were included. Two groups were identified based on self-reports or prenatal or hospital records: women with at least one infection factor and women without any maternal infection (vulvovaginitis, urinary tract infection, or dental infection). A bivariate analysis was performed to identify potential individual risk factors for PTB. The odds ratios (ORs) with their respective 95% confidence intervals were calculated.

RESULTS

The majority of women with sPTB fulfilled at least one criterion for the identification of maternal infection (65.9%), and more than half reported having urinary tract infection during pregnancy. Approximately 9.6% of women with PTB and maternal infection were classified as having periodontal infection only. Apart from the presence of a partner, which was more common among women with infectious diseases (p=0.026; OR, 1.28 [1.03-1.59]), other variables did not show any significant difference between groups.

CONCLUSION

Maternal infection was highly prevalent in all cases of sPTBs, although it was not clearly associated with the type of PTB, gestational age, or any adverse neonatal outcomes.

Transitioning Into the Role of Mother Following the Birth of a Very Low-Birth-Weight Infant: A Grounded Theory Pilot Study

This qualitative grounded theory pilot study investigated the concerns and coping mechanisms of mothers of very low-birth-weight (VLBW; <1500 g) infants following discharge from the neonatal intensive care unit in Alberta, Canada. In-depth, semistructured, face-to-face, audio-recorded interviews were conducted with women of VLBW infants. Interviews lasting 75 to 90 minutes were transcribed verbatim and coded using grounded theory methodology. Data saturation and theoretical redundancy were achieved in interviews with 6 mothers of VLBW infants. The core variable of "reconstructing normal" emerged from the interview data. Women indicated that mothering a VLBW infant is an unfolding experience that is continuously being revised, creating a new sense of normal. The construct consists of 4 categories; mother-infant relationship, maternal development, maternal caregiving and role-reclaiming strategies, and infant developmental milestones. Findings from this study suggest that women found the transition into motherhood following the birth of a VLBW infant as a multidimensional and dynamic process. Further research is warranted to confirm these results and to further explore mothering issues with VLBW infants.

Pilot study to establish a prospective neonatal cohort: Study of Preterm Infants and Neurodevelopmental Genes (SPRING)

BACKGROUND

Genetic risk variants and preterm birth are early and potent risk factors for later neuropsychiatric disorders. To understand the interrelationships between these factors, a large-scale genetic study of very preterm (VPT, <32 weeks gestation) infants with prospective follow-up is required. In this paper, we describe a streamlined study approach, using efficient processes for biological and clinical data collection, to feasibly establish such a cohort.

METHODS

We sought to recruit 500 VPT families within a 1 year period from neonatal units. Treating clinical teams recruited eligible participants, obtained parent consent, collected blood samples and posted specimens to the research laboratory. We extracted all clinical data from the National Neonatal Research Database, an existing UK resource that captures daily patient-level data on all VPT infants.

RESULTS

Between May 2017 and June 2018, we established a cohort of 848 VPT infants and their parents from 60 English neonatal units. The study population (median (IQR), gestation: 28.9 (26-30) weeks; birth weight: 1120 (886-1420) g) represented 18.9% of eligible infants born at the study sites during the recruitment period (n=4491). From the subset of 521 complete family trios, we successfully completed genotyping for 510 (97.9%) trios. Of the original 883 infants whose parents consented to participate, the parents of 796 (90.1%) infants agreed to future data linkage and 794 (89.9%) agreed to be recalled.

CONCLUSION

We demonstrate the feasibility and acceptability of streamlined strategies for genetic, neonatal and longitudinal data collection and provide a template for future cost-effective and efficient cohort development.

Out-of-home care placements of children and adolescents born preterm: A register-based cohort study

BACKGROUND

Preterm birth predisposes to child protection action in the form out-of-home care. The impact of the degree of preterm birth on the likelihood for OHC placement(s) and their timing is unknown.

METHODS

This population-based register-linkage study assessed the likelihood of OHC placement in different gestational age groups using multivariable Cox regression models. All 193 033 traceable singleton (8324 preterm, 4.3%) liveborn in Finland (January 1987-September 1990), as the first index child of each mother within the cohort period, were followed up until their 18th birthday.

RESULTS

A total of 6562 children (3.4%) experienced OHC. In comparison with full-term children (39-41 weeks), those born at 23-33 completed weeks were predisposed to OHC (hazard ratio [HR] 2.11, 95% confidence interval [CI] 1.74, 2.56). For those born late preterm (34-36 weeks) and early term (37-38 weeks), the HR were 1.54 (95% CI 1.37, 1.73) and 1.19 (95% CI 1.12, 1.26), respectively. Adjustment for parental and child characteristics attenuated the HRs: 23-33 weeks: 1.31 (95% CI 1.07, 1.59), 34-36 weeks: 1.17 (95% CI 1.04, 1.31), and 37-38 weeks: 1.08 (95% CI 1.02, 1.16). However, the adjusted HRs for first OHC entries at 0-5 years of age were higher: 23-33 weeks 2.29 (95% CI 1.72, 3.05), 34-36 weeks 1.76 (95% CI 1.46, 2.13), and 37-38 weeks 1.40 (95% CI 1.25, 1.56). Among those born preterm or early term, in comparison with their term born peers, no excess risk for OHC was seen after 5 years.

CONCLUSIONS

A dose-response relationship exists between the level of preterm birth and OHC placement risk. OHC placements are more common among early and late preterm, and early term children, compared with those born full term, and occur at younger age. Perinatal and postnatal adverse circumstances appear to explain the phenomenon only partly.

Optimal Ventilation and Surfactant Therapy in Very-Low-Birth-Weight Infants in Resource-Restricted Regions

In resource-restricted regions, respiratory distress syndrome (RDS) data are often underreported, making the determination of effective interventions and their outcome difficult. The combination of oxygen, nasal continuous positive airway pressure (CPAP) and surfactant therapy has the potential to prevent 42% of RDS-related deaths in sub-Saharan Africa, despite the financial implications. This article provides a brief overview on the status of RDS management, mainly nasal CPAP and surfactant therapy in very-low-birth-weight infants, in resource-restricted regions of sub-Saharan Africa. Data from the public health sector, as compared to the private health sector, of the Western Cape province, South Africa, are used to illustrate what RDS management strategies are able to accomplish in a resource-restricted region. Upscaling of all components (antenatal care, antenatal corticosteroids, prevention of hypothermia and RDS management strategies) are required to decrease premature infant mortality rates in resource-restricted areas.

Evidence that informs feeding practices in very low birthweight and very preterm infants in sub-Saharan Africa: an overview of systematic reviews

BACKGROUND

Optimal feeding of very low birthweight (VLBW <1500 g)/very preterm (gestation <32 weeks) infants in resource-limited settings in sub-Saharan Africa (sSA) is critical to reducing high mortality and poor outcomes.

OBJECTIVE

To review evidence on feeding of VLBW/very preterm infants relevant to sSA.

METHODS

We searched the Cochrane Database of Systematic Reviews, Embase, PubMed and Cumulative Index to Nursing and Allied Health Literature (CINAHL) from inception to July 2019 to identify reviews of randomised and quasi-randomised controlled trials of feeding VLBW/very preterm infants. We focused on interventions that are readily available in sSA. Primary outcomes were weight gain during hospital stay and time to achieve full enteral feeds (120 mL/kg/day). Secondary outcomes were growth, common morbidities, mortality, duration of hospital stay and cognitive development. Quality of evidence (QOE) was assessed using the Measurement Tool to Assess Systematic Reviews (AMSTAR2).

RESULTS

Eight systematic reviews were included. Higher feed volume of day 1 (80 mL/kg) reduced late-onset sepsis and time to full enteral feeds, and higher feed volume (up to 300 mL/kg/day) improved weight gain without adverse events (QOE: low-moderate). Rapid advancement of feeds (30-40 mL/kg/day) was not associated with harm. Breast milk fortification with energy and protein increased growth and with prebiotics increased growth and reduced duration of admission (QOE: low-very low) and did not result in harm. Evidence regarding feeding tube placement and continuous versus bolus feeds was insufficient to draw conclusions. We found no reviews meeting our selection criteria regarding when to start feeds, use of preterm formula, cup-and-spoon feeding or gravity versus push feeds and none of the reviews included trials from low-income countries of sSA.

CONCLUSIONS

The evidence base informing feeding of VLBW/very preterm babies in resource-limited settings in sSA is extremely limited. Pragmatic studies are needed to generate evidence to guide management and improve outcomes for these highly vulnerable infants.

PROSPERO REGISTRATION NUMBER

CRD42019140204.

The Life Course Consequences of Very Preterm Birth

Around 15 million children are born preterm (<37 weeks of gestation) every year. Of these, 15% or 2.25 million are born very preterm (VP; <32 weeks of gestation). Here, the developmental outcomes of VP babies in diverse domains from motor, cognitive, and social function to mental health and well-being throughout childhood and adolescence are reviewed. Their life course adaptation in terms of romantic relationships, employment, and quality of life into adulthood is also considered. Some adverse effects reduce as individuals age, and others remain remarkably stable from childhood into adulthood. We argue that to advance understanding of developmental mechanisms and direct resources for intervention more effectively, social factors need to be assessed more comprehensively, and genetically sensitive designs should be considered with neuroimaging integrated to test alternative developmental models. As current evidence is based almost exclusively on studies from high-income countries, research from low- and middle-income countries is urgently needed.

Retinopathy of Prematurity and Bronchopulmonary Dysplasia are Independent Antecedents of Cortical Maturational Abnormalities in Very Preterm Infants

Very preterm (VPT) infants are at high-risk for neurodevelopmental impairments, however there are few validated biomarkers at term-equivalent age that accurately measure abnormal brain development and predict future impairments. Our objectives were to quantify and contrast cortical features between full-term and VPT infants at term and to associate two key antecedent risk factors, bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP), with cortical maturational changes in VPT infants. We prospectively enrolled a population-based cohort of 110 VPT infants (gestational age ≤31 weeks) and 51 healthy full-term infants (gestational age 38-42 weeks). Structural brain MRI was performed at term. 94 VPT infants and 46 full-term infants with high-quality T2-weighted MRI were analyzed. As compared to full-term infants, VPT infants exhibited significant global cortical maturational abnormalities, including reduced surface area (-5.9%) and gyrification (-6.7%) and increased curvature (5.9%). In multivariable regression controlled for important covariates, BPD was significantly negatively correlated with lobar and global cortical surface area and ROP was significantly negatively correlated with lobar and global sulcal depth in VPT infants. Our cohort of VPT infants exhibited widespread cortical maturation abnormalities by term-equivalent age that were in part anteceded by two of the most potent neonatal diseases, BPD and ROP.

Developmental Outcomes of Preterm and Low Birth Weight Toddlers and Term Peers in Rwanda

Background:

As neonatal care improves in low-resource settings, more preterm or low birth weight (LBW) babies are surviving, but little is known about their long-term outcomes. Globally, preterm and/or LBW babies are at increased risk of mortality, malnutrition, and developmental delay.

Objectives:

We aim to describe the differences in development in rural Rwandan children at 24–36 months of age born preterm and/or LBW compared to their peers born term or normal birth weight (term/NBW), and to assess factors associated with poor development.

Methods:

We conducted a cross-sectional study using secondary data analysis from two combined datasets from 2014, using Ages and Stages Questionnaire (ASQ-3) for developmental assessment and anthropometrics for nutritional status (stunting and wasting). Demographic and clinical factors associated with poor developmental outcomes in univariate regression at α = 0.20 were included in a full model; we used backward stepwise penalized multivariable logistic regression to identify a final model at α = 0.05.

Findings:

In total, 445 children were included; 405 term/NBW, and 40 preterm and/or LBW. Half of them (n = 234; 52.6%) had developmental delay, including 207 (51.1%) among term/NBW and 27 (67.5%) among preterm and/or LBW (p = 0.048). In the final model, term/NBW children with stunting alone had a significant increase in the odds of developmental delay (OR 2.05, 95% CI 1.37–3.07), and children with wasting had a borderline statistically significant increased odds of developmental delay (OR 5.79, 95% CI 0.98-34.39). Being preterm and/or LBW and not stunted completely predicted delay.

Conclusion:

Half of the children had developmental delay in our sample from rural Rwanda. Preterm and/or LBW infants were more likely to have developmental delay, and the main predictor of developmental delay was stunting, with high rates of stunting observed also in term/NBW infants. Interventions to reduce undernutrition and prevent prematurity and LBW, alongside investments to promote early stimulation for optimal development, are needed if gains in addressing developmental delay are to be made.

Invited Review: Factors associated with atypical brain development in preterm infants: insights from magnetic resonance imaging

Preterm birth (PTB) is a leading cause of neurodevelopmental and neurocognitive impairment in childhood and is closely associated with psychiatric disease. The biological and environmental factors that confer risk and resilience for healthy brain development and long‐term outcome after PTB are uncertain, which presents challenges for risk stratification and for the discovery and evaluation of neuroprotective strategies. Neonatal magnetic resonance imaging reveals a signature of PTB that includes dysconnectivity of neural networks and atypical development of cortical and deep grey matter structures. Here we provide a brief review of perinatal factors that are associated with the MRI signature of PTB. We consider maternal and foetal factors including chorioamnionitis, foetal growth restriction, socioeconomic deprivation and prenatal alcohol, drug and stress exposures; and neonatal factors including co‐morbidities of PTB, nutrition, pain and medication during neonatal intensive care and variation conferred by the genome/epigenome. Association studies offer the first insights into pathways to adversity and resilience after PTB. Future challenges are to analyse quantitative brain MRI data with collateral biological and environmental data in study designs that support causal inference, and ultimately to use the output of such analyses to stratify infants for clinical trials of therapies designed to improve outcome.

Effects of prenatal exposure to air particulate matter on the risk of preterm birth and roles of maternal and cord blood LINE-1 methylation: A birth cohort study in Guangzhou, China

BACKGROUND

Epidemiological studies have found that increased risk of preterm birth (PTB) is associated with higher prenatal exposure to PM₁₀ and PM_2.5, but few studies have been conducted to assess the impacts of extremely fine particulate matter (PM₁) which may have more toxic effects than other types of ambient particulate air pollution (PM). Several studies have separately investigated the associations between DNA methylation and PTB risk and PM. Maternal LINE-1 methylation level negatively correlated with prenatal exposure to PM and risk of PTB. A comprehensive picture is lacking regarding the associations between prenatal exposure to PM, LINE-1 methylation, and risk of PTB.

OBJECTIVES

This study aimed to estimate the effects of exposure to ambient PM (PM₁₀, PM_2.5, and PM₁) of different sizes during pregnancy on risk of PTB, identify susceptible exposure windows, and illustrate the roles of LINE-1 methylation in the associations between PM and PTB risk.

METHODS

The Birth Cohort Study on Prenatal Environments and Offspring Health (PEOH) has been ongoing since 2016 in Guangzhou, China. A total of 4928 pregnant women were recruited during early pregnancy, and 4278 (86.8%) were successfully followed-up. Each individual weekly exposure to PM₁₀ and PM_2.5 from 3 months before pregnancy to childbirth was assessed using a spatiotemporal land use regression model, and the weekly PM₁ exposure was estimated by employing a generalized additive model. Maternal and cord blood LINE-1 methylation levels (%5mC) were tested using bisulfite-PCR pyrosequencing. A distributed lag nonlinear model incorporated with a Cox proportional hazard model was applied to assess the effect of weekly-specific maternal PM exposure on PTB risk, and a multiple-linear regression model was employed to investigate the associations between PM exposure and LINE-1 methylation levels of maternal and cord bloods. We also assessed the associations between LINE-1 methylation levels and PTB risk by using a logistic regression model.

RESULTS

The risk of PTB was positively associated with PM_2.5 and PM₁ concentrations during the 12th to 20th gestational weeks, and the strongest association was in the fourth quartile (Q₄) versus the first quartile (Q₁) and observed during the 16th gestational week (PM_2.5: harzard ratio [HR] = 1.18, 95%CI: 1.04-1.35, IQR = 11.94 μg/m³. PM₁: HR = 1.20, 95%CI: 1.03-1.39, IQR = 11.36 μg/m³). We observed significantly negative associations of PM₁₀(β = -0.51%5mC per 10 μg/m³, P = 0.014), PM_2.5 (β = -0.66%5mC per 10 μg/m³, P = 0.032) and PM₁ (β = -0.67%5mC per 10 μg/m³, P = 0.032) concentrations with cord blood LINE-1 methylation levels, and a negative association between PM₁ concentration and maternal LINE-1 methylation level (β = -0.86%5mC per 10 μg/m³, P = 0.034).

CONCLUSION

Higher prenatal exposure to PM₁ and PM_2.5 during the 12th to 20th gestational weeks was associated with increased risk of PTB. Maternal and fetal LINE-1 methylation alternation might be an underlying mechanism of PM that increasing the risk of PTB.

Association between HIV antiretroviral therapy and preterm birth based on antenatal ultrasound gestational age determination: a comparative analysis

OBJECTIVE

To evaluate the association between HIV antiretroviral therapy (ART) and preterm birth (PTB), when defined by gold standard antenatal ultrasound versus newborn exam.

DESIGN

A secondary analysis of the PROMISE 1077BF/1077FF randomized controlled trial, which compared antiretroviral strategies to reduce perinatal HIV transmission and improve maternal health. The trial used newborn exam (i.e. New Ballard Score, NBS) to assess gestational age. This analysis included liveborn singleton pregnancies with both newborn exam and ultrasound data. The primary exposure was the trial's antiretroviral strategies: zidovudine with intrapartum nevirapine ('ZDV alone'); zidovudine/lamivudine/lopinavir-ritonavir ('ZDV-based ART'); or tenofovir/emtricitabine/lopinavir-ritonavir ('TDF-based ART'). The primary outcome was PTB less than 37 and less than 34 weeks based on the gold standard of ultrasound dating. We evaluated the association between antiretroviral strategy and PTB. We fit multivariable logistic regression models, adjusting for maternal characteristics, obstetric history, and HIV disease severity.

RESULTS

Among 720 assessed pregnant women, PTB less than 37 weeks was 15.4% by NBS and 18.3% by ultrasound. The NBS was specific but not sensitive for PTB less than 37 weeks (92.0% and 48.5%). Women receiving ZDV-based and TDF-based ART had significantly higher odds of PTB less than 37 by ultrasound compared with ZDV alone (adjusted odds ratios: 1.68; 95% confidence interval 1.10-2.57, and 2.71; 95% confidence interval 1.39-5.29), as well as for PTB less than 34 weeks. These results held for ultrasounds performed less than 24 weeks, and were generally consistent with prior analyses from the PROMISE trial using the NBS.

CONCLUSION

Women starting HIV ART in pregnancy remained at higher risk of PTB when determined by ultrasound, consistent with prior data using newborn exam. However, newborn exam misclassified cases of PTB compared with gold standard ultrasound.

Monitoring maternal and newborn health outcomes globally: a brief history of key events and initiatives

OBJECTIVE

Over time, we have seen a major evolution of measurement initiatives, indicators and methods, such that today a wide range of maternal and perinatal indicators are monitored and new indicators are under development. Monitoring global progress in maternal and newborn health outcomes and development has been dominated in recent decades by efforts to set, measure and achieve global goals and targets: the Millennium Development Goals followed by the Sustainable Development Goals. This paper aims to review, reflect and learn on accelerated progress towards global goals and events, including universal health coverage, and better tracking of maternal and newborn health outcomes.

METHODS

We searched for literature of key events and global initiatives over recent decades related to maternal and newborn health. The searches were conducted using PubMed/MEDLINE and the World Health Organization Global Index Medicus.

RESULTS

This paper describes global key events and initiatives over recent decades showing how maternal and neonatal mortality and morbidity, and stillbirths, have been viewed, when they have achieved higher priority on the global agenda, and how they have been measured, monitored and reported. Despite substantial improvements, the enormous maternal and newborn health disparities that persist within and between countries indicate the urgent need to renew the focus on reducing inequities.

CONCLUSION

The review has featured the long story of the progress in monitoring improving maternal and newborn health outcomes, but has also underlined current gaps and significant inequities. The many global initiatives described in this paper have highlighted the magnitude of the problems and have built the political momentum over the years for effectively addressing maternal and newborn health and well-being, with particular focus on improved measurement and monitoring.

Risk of particulate matter on birth outcomes in relation to maternal socio-economic factors: a systematic review

A growing number of studies provide evidence of an association between exposure to maternal air pollution during pregnancy and adverse birth outcomes including low birth weight and preterm birth. Prevention of these health effects of air pollution is critical to reducing the adverse infant outcomes, which can have impacts throughout the life course. However, there is no consensus on whether the association between air pollution exposure and birth outcomes varies by maternal risk factors including demographic characteristics and socio-economic status. Such information is vital to understand potential environmental health disparities. Our search found 859 unique studies, of which 45 studies met our inclusion criteria (Jan. 2000- July. 2019). We systematically reviewed the 45 identified epidemiologic studies and summarized the results on effect modifications by maternal race/ethnicity, educational attainment, income, and area-level socio-economic status. We considered adverse birth outcomes of preterm birth, low birth weight, small for gestational age (SGA), and stillbirth. Suggestive evidence of higher risk of particulate matter in infants of African-American/black mothers than infants of other women was found for preterm birth and low birth weight. We found weak evidence that particulate matter risk was higher for infants of mothers with lower educational attainment for preterm birth and low birth weight. Due to the small study numbers, we were unable to conclude whether effect modification is present for income, occupation, and area-level socio-economic status, and additional research is needed. Furthermore, adverse birth outcomes such as SGA and stillbirth need more study to understand potential environmental justice issues regarding the impact of particulate matter exposure during pregnancy on birth outcomes.

Testing an infection model to explain excess risk of preterm birth with long-term iron supplementation in a malaria endemic area

Background

In view of recent evidence from a randomized trial in Burkina Faso that periconceptional iron supplementation substantially increases risk of spontaneous preterm birth (< 37 weeks) in first pregnancies (adjusted relative risk = 2.22; 95% CI 1.39–3.61), explanation is required to understand potential mechanisms, including progesterone mediated responses, linking long-term iron supplementation, malaria and gestational age.

Methods

The analysis developed a model based on a dual hit inflammatory mechanism arising from simultaneous malaria and gut infections, supported in part by published trial results. This model is developed to understand mechanisms linking iron supplementation, malaria and gestational age. Background literature substantiates synergistic inflammatory effects of these infections where trial data is unavailable. A path modelling exercise assessed direct and indirect paths influencing preterm birth and gestation length.

Results

A dual hit hypothesis incorporates two main pathways for pro-inflammatory mechanisms, which in this model, interact to increase hepcidin expression. Trial data showed preterm birth was positively associated with C-reactive protein (P = 0.0038) an inflammatory biomarker. The malaria pathway upregulates C-reactive protein and serum hepcidin, thereby reducing iron absorption. The enteric pathway results from unabsorbed gut iron, which induces microbiome changes and pathogenic gut infections, initiating pro-inflammatory events with lipopolysaccharide expression. Data from the trial suggest that raised hepcidin concentration is a mediating catalyst, being inversely associated with shorter gestational age at delivery (P = 0.002) and positively with preterm incidence (P = 0.007). A segmented regression model identified a change-point consisting of two segments before and after a sharp rise in hepcidin concentration. This showed a post change hepcidin elevation in women with increasing C-reactive protein values in late gestation (post-change slope 0.55. 95% CI 0.39–0.92, P < 0.001). Path modelling confirmed seasonal malaria effects on preterm birth, with mediation through C-reactive protein and (non-linear) hepcidin induction.

Conclusions

Following long-term iron supplementation, dual inflammatory pathways that mediate hepcidin expression and culminate in progesterone withdrawal may account for the reduction in gestational age observed in first pregnancies in this area of high malaria exposure. If correct, this model strongly suggests that in such areas, effective infection control is required prior to iron supplementation to avoid increasing preterm births.

Trial registration NCT01210040. Registered with Clinicaltrials.gov on 27th September 2010

Immunomodulatory Effects of Vitamin D in Pregnancy and Beyond

In addition to its role in calcium homeostasis and bone formation, a modulatory role of the active form of vitamin D on cells of the immune system, particularly T lymphocytes, has been described. The effects of vitamin D on the production and action of several cytokines has been intensively investigated in recent years. In this connection, deficiency of vitamin D has been associated with several autoimmune diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), antiphospholipid syndrome (APS), Hashimoto Thyroiditis (HT), and multiple sclerosis (MS). In a successful pregnancy, the maternal immune response needs to adapt to accommodate the semiallogeneic fetus. Disturbances in maternal tolerance are implicated in infertility and pregnancy complications such as miscarriages (RM) and preeclampsia (PE). It is well-known that a subset of T lymphocytes, regulatory T cells (Tregs) exhibit potent suppressive activity, and have a crucial role in curtailing the destructive response of the immune system during pregnancy, and preventing autoimmune diseases. Interestingly, vitamin D deficiency is common in pregnant women, despite the widespread use of prenatal vitamins, and adverse pregnancy outcomes such as RM, PE, intrauterine growth restriction have been linked to hypovitaminosis D during pregnancy. Research has shown that autoimmune diseases have a significant prevalence within the female population, and women with autoimmune disorders are at higher risk for adverse pregnancy outcomes. Provocatively, dysregulation of T cells plays a crucial role in the pathogenesis of autoimmunity, and adverse pregnancy outcomes where these pathologies are also associated with vitamin D deficiency. This article reviews the immunomodulatory role of vitamin D in autoimmune diseases and pregnancy. In particular, we will describe the role of vitamin D from conception until delivery, including the health of the offspring. This review highlights an observational study where hypovitaminosis D was correlated with decreased fertility, increased disease activity, placental insufficiency, and preeclampsia in women with APS.