Size for gestational age at birth: impact on risk for sudden infant death and other causes of death, USA 2002

Small for gestational age in twin pregnancies and the risk of offspring pediatric neurologic morbidity

OBJECTIVES

Small for gestational age (SGA) singletons are at increased risk for neurodevelopmental abnormalities. Scarce data exist regarding the long-term implications of SGA in twins. We opted to study the association between SGA of one twin and long-term neurologic related morbidity in dichorionic diamniotic twins.

STUDY DESIGN

A population-based retrospective cohort study including consecutive dichorionic diamniotic twins, born between the years 1991 and 2021 at a tertiary medical center was conducted. Total and subtypes of neurologic related pediatric hospitalizations among SGA versus non-SGA twins were compared. A Kaplan-Meier survival curve was used to compare the cumulative neurologic morbidity incidence, and a Cox proportional hazards model was constructed to adjust for confounders.

RESULTS

The study population included 4222 newborns; 180 (4.3%) were SGA. Rate of long-term neurologic related hospitalizations was comparable between the two groups (8.7 vs. 8.0%, p = 0.755; Kaplan-Meier survival curve Log-rank p = 0.652). Using a Cox proportional hazards model, controlling for gender and birth order, no association was found between SGA and the risk for subsequent neurologic pediatric morbidity of the offspring (Adjusted HR = 1.0, 95% CI 0.6-1.8, p = 0.973).

CONCLUSIONS

SGA is not associated with an increased risk for long-term pediatric neurologic morbidity in dichorionic diamniotic twins.

Newborn auditory brainstem response and sudden infant death syndrome

Sudden infant death syndrome (SIDS)-the sudden and unexplained death of a seemingly healthy infant, <1 year old-may be associated with abnormalities in the brain regions that underlie breathing and arousal during sleep. While post-mortem studies suggest abnormalities in SIDS infants' brainstems, there are no studies of these infants' brainstem function before death. One way to assess the function of the brainstem is with auditory brainstem response (ABR), a routine hearing-screening method that noninvasively measures the brainstem's response to sound. We hypothesize that anomalies in newborns' ABR measures may predict SIDS. Indeed, previous studies identified abnormalities in ABR characteristics in small samples of near-miss SIDS infants hospitalized for infant apnea syndrome. However, there is a need to examine the ABRs of infants who died of SIDS. Therefore, in the current study, we propose integrating two secondary datasets to examine newborns' ABRs (N = 156,972), including those who later died of SIDS (n = ~42; .27 out of every 1000 infants), using existing archived records of neonatal ABR results from a sample of newborns born in Florida. We hypothesize that infants who die from SIDS are more likely than non-SIDS infants to have abnormal ABRs as newborns. Understanding the association between SIDS and ABR may facilitate more accurate identification of an infant's risk for SIDS at birth, enabling increased monitoring, which may facilitate interventions and improve survivorship.

Postneonatal mortality of severely small for gestational age extremely low birth weight infants

BACKGROUND

Infants born with weights below the 10th percentile of the expected birth weight for gestational age, defined as small for gestational age (SGA), have an increased risk of neonatal mortality and prematurity-related complications. However, the relationship between SGA and postneonatal (28 days to <1 year) mortality among extremely low birth weight infants (ELBWIs) remains uncertain. Hence, this study aimed to investigate the association between birth weight percentiles and postneonatal mortality in ELBWIs.

METHODS

A cohort of ELBWIs with a gestational age greater than 23 weeks who were admitted to Osaka Women's and Children's Hospital between 2008 and 2019 were considered eligible. Infants with major congenital anomalies, those large for their gestational age, or those who died within 28 days of birth were excluded. Baseline characteristics and outcomes of the three groups of ELBWIs-severe SGA (sSGA; birth weight, <3rd percentile), moderate SGA (mSGA; birth weight, 3rd to <10th percentile), and appropriate for gestational age (AGA; birth weight, 10th to <90th percentile)-were compared. Logistic regression analysis was used to identify perinatal factors associated with postneonatal mortality in sSGA infants.

RESULTS

sSGA ELBWIs demonstrated higher incidence of meconium obstruction (25% vs. 8.3% vs. 7.6%, P < 0.001), cholestasis (21% vs. 4.2% vs. 9.7%, P < 0.003), and postneonatal mortality (7.3% vs. 0% vs. 0.7%, P < 0.004) than mSGA and AGA ELBWIs. In the logistic regression analysis, cholestasis (odds ratio, 30.1; 95% confidence interval, 2.98-304) and sepsis (odds ratio, 13.5; 95% confidence interval, 1.06-173) were significantly related to postneonatal mortality among ELBWIs with sSGA. The leading cause of postneonatal mortality in sSGA ELBWIs was liver failure (55.5%).

CONCLUSION

sSGA ELBWIs exhibited a higher rate of postneonatal mortality compared to mSGA and AGA ELBWIs. Therefore, strategies aimed at preventing liver dysfunction in severely cholestatic ELBWIs with sSGA are necessary.

Maternal socioeconomic and lifestyle factors and life dissatisfaction associated with a small for gestational age infant. The Survey of Neonates in Pomerania (SNiP)

PURPOSE

The aim is to investigate the associations of the mother's socioeconomic and lifestyle factors and life satisfaction with the delivery of a small for gestational age (SGA) infant.

METHODS

Data from 4598 participants of the population-based birth cohort study Survey of Neonates in Pomerania (SniP) including comprehensive information on pregnancies, mothers, and their offspring in Western Pomerania, Germany were used in this study. The associations were analyzed using linear and logistic regression models.

RESULTS

After logistic regression analysis adjusted for height of the mother, women who delivered SGA infants, had lower education (p < 0.01) and smoked more frequently during pregnancy (p < 0.01) compared with mothers of adequate for gestational age (AGA) neonates. A mother with less than 10 years of education and one who continued smoking during pregnancy had an odds ratio (OR) of 2.23 [95% confidence interval (CI) = 1.44 to 3.46] and 2.68 (95% CI = 2.06-3.49) of having an SGA infant, respectively. There was no association between the employment of the mother (p = 0.28), the monthly income (p = 0.09), the family status (p = 0.80), the number of friendships outside the household that the mother would not wish to relinquish (p = 0.47), the number of people that she could rely on in case of an emergency (p = 0.75), or alcohol consumption prior to (p = 0.14) or during the pregnancy (p = 0.99) with SGA. Finally, women who delivered SGA infants were more frequently dissatisfied with their employment (p = 0.03) and financial status (p < 0.01).

CONCLUSIONS

Women who delivered SGA infants had more associated socioeconomic and lifestyle risk factors and were more frequently dissatisfied with their life conditions than mothers of AGA neonates.

Medically assisted reproduction and the risk of being born small and very small for gestational age: Assessing prematurity status as an effect modifier

Over the last decade, the use of medically assisted reproduction (MAR) has steadily increased but controversy remains with regards to its risks. We aimed to quantify the risk of being born small for gestational age (SGA) and very SGA (VSGA) associated with MARs overall and by type, namely ovarian stimulators (OS) and assisted reproductive technology (ART). We conducted a cohort study within the Quebec Pregnancy Cohort. Pregnancies coinciding with Quebec’s MAR reimbursement PROGRAM period (2010–2014) with a singleton liveborn were considered. MAR was first defined dichotomously, using spontaneous conception as the reference, and categorized into three subgroups: OS alone (categorized as clomiphene and non-clomiphene OS), ART, OS/ART combined. SGA was defined as being born with a birth weight below the 10th percentile based on sex and gestational age (GA), estimated using populational curves in Canada, while VSGA was defined as being born with a birth weight below the 3rd percentile. We then estimated odds ratios (OR) for the association between MAR and SGA as well as VSGA using generalized estimated equation (GEE) models, adjusted for potential confounders (aOR). Two independent models were conducted considering MAR exposure overall, and MAR subgroup categories, using spontaneous conceptions as the reference. The impact of prematurity status (less than 37 weeks gestation) as an effect modifier in these associations was assessed by evaluating them among term and preterm pregnancies separately. A total of 57,631 pregnancies met inclusion criteria and were considered. During the study period, 2,062 women were exposed to MARs: 420 to OS alone, 557 to ART, and 1,085 to OS/ART combined. While no association was observed between MAR and SGA nor VSGA in the study population, MAR was associated with an increased risk for SGA (aOR 1.69, 95% CI 1.08–2.66; 25 exposed cases) among preterm pregnancies; no increased risk of SGA was observed in term pregnancies. MARs are known to increase the risk of preterm birth and our results further confirm that they also increase the risk of SGA among preterm pregnancies.

Development of a Risk Score to Predict Sudden Infant Death Syndrome

Sudden Infant Death Syndrome (SIDS) is the third leading cause of death among infants younger than one year of age. Effective SIDS prediction models have yet to be developed. Hence, we developed a risk score for SIDS, testing contemporary factors including infant exposure to passive smoke, circumcision, and sleep position along with known risk factors based on 291 SIDS and 242 healthy control infants. The data were retrieved from death certificates, parent interviews, and medical records collected between 1989−1992, prior to the Back to Sleep Campaign. Multivariable logistic regression models were performed to develop a risk score model. Our finalized risk score model included: (i) breastfeeding duration (OR = 13.85, p < 0.001); (ii) family history of SIDS (OR = 4.31, p < 0.001); (iii) low birth weight (OR = 2.74, p = 0.003); (iv) exposure to passive smoking (OR = 2.64, p < 0.001); (v) maternal anemia during pregnancy (OR = 2.07, p = 0.03); and (vi) maternal age <25 years (OR = 1.77, p = 0.01). The area under the curve for the overall model was 0.79, and the sensitivity and specificity were 79% and 63%, respectively. Once this risk score is further validated it could ultimately help physicians identify the high risk infants and counsel parents about modifiable risk factors that are most predictive of SIDS.

Parity-Adjusted Term Neonatal Growth Chart Modifies Neonatal Morbidity and Mortality Risk Stratification

Objective: To investigate the impact of parity-customized versus population-based birth weight charts on the identification of neonatal risk for adverse outcomes in small (SGA) or large for gestational age (LGA) infants compared to appropriate for gestational age (AGA) infants. Study design: Observational, retrospective, cohort study based on electronic medical birth records at a single center between 2006 and 2017. Neonates were categorized by birth weight (BW) as SGA, LGA, or AGA, with the 10th and 90th centiles as boundaries for AGA in a standard population-based model adjusted for gestational age and gender only (POP) and a customized model adjusted for gestational age, gender, and parity (CUST). Neonates defined as SGA or LGA by one standard and not overlapping the other, are SGA/LGA CUST/POP ONLY. Analyses used a reference group of BW between the 25th and 75th centile for the population. Results: Overall 132,815 singleton, live, term neonates born to mothers with uncomplicated pregnancies were included. The customized model identified 53% more neonates as SGA-CUST ONLY who had significantly higher rates of morbidity and mortality compared to the reference group (OR = 1.33 95% CI [1.16−1.53]; p < 0.0001). Neonates defined as LGA by the customized model (LGA-CUST) and AGA by the population-based model LGA-CUST ONLY had a significantly higher risk for morbidity compared to the reference (OR = 1.36 95% CI [1.09−1.71]; p = 0.007) or the LGA POP group. Neonatal mortality only occurred in the SGA and AGA groups. Conclusions: The application of a parity-customized only birth weight chart in a population of singleton, term neonates is a simple platform to better identify birth weight related neonatal risk for morbidity and mortality.

Estimation of neonatal body fat percentage predicts neonatal hypothermia better than birthweight centile

INTRODUCTION

PEA POD™ air displacement plethysmography quickly and noninvasively estimates neonatal body fat percentage (BF%). Low PEA POD™ BF% predicts morbidity better than classification as small-for-gestational-age (SGA; <10th centile), but PEA PODs are not widely available. We examined whether skinfold measurements could effectively identify neonates at risk; comparing skinfold BF%, PEA POD™ BF% and birthweight centiles' prediction of hypothermia - a marker of reduced in utero nutrition.

METHODS

Neonates had customized birthweight centiles calculated, and BF% prospectively estimated by: (i) triceps and subscapular skinfolds using sex-specific equations; and (ii) PEA POD™. Medical record review identified hypothermic (<36.5 °C) episodes.

RESULTS

42/149 (28%) neonates had hypothermia. Skinfold BF%, with an area under the curve (AUC) of 0.66, predicted hypothermia as well as PEA POD™ BF% (AUC = 0.62) and birthweight centile (AUC = 0.61). Birthweight <10^th centile demonstrated 11.9% sensitivity, 38.5% positive predictive value (PPV) and 92.5% specificity for hypothermia. At equal specificity, skinfold and PEA POD™ BF% more than doubled sensitivity (26.2%) and PPV increased to 57.9%.

CONCLUSION

Neonatal BF% performs better to predict neonatal hypothermia than birthweight centile, and may be a better measure of true fetal growth restriction. Estimation of neonatal BF% by skinfold measurements is an inexpensive alternative to PEA POD™.

What is the impact of birth weight corrected for gestational age on later onset asthma: a meta-analysis

Background

Asthma is a common multifactorial disease affecting millions worldwide. The Barker hypothesis postulates an association between later onset disease risk and energy exposure in utero. Birth weight corrected for gestational age is better for measuring the infant size, which reflects energy exposure in utero. Findings on asthma and birth weight corrected for gestational age have been inconclusive. We conducted a meta-analysis to further clarify the relationship between birth weight corrected for gestational age and later onset asthma.

Methods

A systematic literature search of the PubMed, Web of Science, MEDLINE, and Scopus databases up to January 2021 was conducted. The subject terms were used as follows: “asthma”, “allerg*”, “respiratory”, “birth weight”, “gestational age”, “birth outcomes”, “intrauterine growth retardation”, and “fetal growth restriction”.

Results

We included 12 articles with data from a total of 6,713,596 people. Compared with non-SGA infants, infants small for gestation age (SGA) were not associated with an increased risk of asthma (OR = 1.07; 95% CI 0.94–1.21). However, in the subgroup analysis, we found an increased risk of later onset asthma among SGA in studies conducted in Asia, with a large sample size, and defined asthma through medical records rather than questionnaires. Large for gestational age (LGA) was not associated with an increased risk of asthma when non-LGA or appropriated for gestational age (AGA) infants were used as the reference (OR = 1.02; 95% CI 0.90–1.16; OR = 1.01; 95% CI 0.88–1.15).

Conclusion

These results indicated that neither SGA nor LGA was associated with an increased risk of asthma. However, considering the limitations of the research, these results should be interpreted with caution.

What risk factors for sudden infant death syndrome are preterm and term medically complex infants exposed to at home?

OBJECTIVES

Risk factors for sudden infant death syndrome include premature birth, maternal smoking, prone or side sleeping position, sleeping with blankets, sharing a sleeping surface with an adult, and sleeping without an adult in the room. In this study, we compare parents' responses on sleep patterns in premature and term infants with medical complexity.

METHODS

Parents of children enrolled in the Canadian Respiratory Syncytial Virus Evaluation Study of Palivizumab were phoned monthly regarding their child's health status until the end of each respiratory syncytial virus season. Baseline data were obtained on patient demographics, medical history, and neonatal course. Responses on adherence to safe sleep recommendations were recorded as part of the assessment.

RESULTS

A total of 2,526 preterms and 670 term infants with medical complexity were enrolled. Statistically significant differences were found in maternal smoking rates between the two groups: 13.3% (preterm); 9.3% (term) infants (χ 2=8.1, df=1, P=0.004) and with respect to toys in the crib: 12.3% (term) versus 5.8% preterms (χ 2=24.5, df=1, P<0.0005). Preterm infants were also significantly more likely to be placed prone to sleep (8.8%), compared with term infants (3.3%), (χ 2=18.1, df=1, P<0.0005).

CONCLUSION

All the infants in this study had frequent medical contacts. There is a greater prevalence of some risk factors for sudden infant death syndrome in preterm infants compared to term infants with medical complexity. Specific educational interventions for vulnerable infants may be necessary.

Association of Antidepressant Continuation in Pregnancy and Infant Birth Weight

PURPOSE

The aim of the study was to evaluate the association of antidepressant continuation in pregnancy with infant birth weight among women using antidepressants before pregnancy.

METHODS

This retrospective cohort study used electronic health data linked with state birth records. We identified singleton live births (2001-2014) to enrolled women with 1 or more antidepressant prescriptions filled 6 months or less before pregnancy, including "continuers" (≥1 antidepressant fills during pregnancy, n = 1775) and "discontinuers" (no fill during pregnancy, n = 1249). We compared birth weight, small or large for gestational age (SGA or LGA), low birth weight (LBW; <2500 g), and macrosomia (>4500 g) between the 2 groups, using inverse probability of treatment weighting to account for pre-pregnancy characteristics, including mental health conditions.

RESULTS

After weighting, infants born to antidepressant continuers weighed 71.9 g less than discontinuers' infants (95% confidence interval [CI], -115.5 to -28.3 g), with a larger difference for female infants (-106.4 g; 95% CI, -164.6 to -48.1) than male infants (-48.5 g; 95% CI, -107.2 to 10.3). For female infants, SGA risk was greater in continuers than discontinuers (relative risk [RR],1.54; 95% CI, 1.02 to 2.32). Low birth weight risk was greater in continuers with 50% or more of days covered (RR, 1.69; 95% CI, 1.11 to 2.58) and exposure in the second trimester (RR, 1.53; 95% CI, 1.02 to 2.29), as compared with discontinuers.

CONCLUSIONS

Depending on infant sex, as well as duration and timing of use, continuation of antidepressant use during pregnancy may be associated with lower infant birth weight, with corresponding increases in LBW and SGA.

Obstetricians' and Gynecologists' Communication Practices around Smoking Cessation in Pregnancy, Secondhand Smoke and Sudden Infant Death Syndrome (SIDS): A Survey

Secondhand smoke (SHS) is a potential direct cause of Sudden Infant Death Syndrome (SIDS) among infants. Disparities in SHS exposure and SIDS deaths may be due to inconsistent communication among practitioners about SHS/SIDS risks. In order to assess current SHS/SIDS risks and communication practices and to identify areas of improvement, we conducted a survey of 316 obstetricians and gynecologists (ob/gyns) about the length of time spent having discussions, supplemental materials used, risks covered, cessation, and frequency of discussions. Most (55.3%) reported spending 1-4 min discussing risks/cessation. Nearly a third reported not using any supplemental materials; few used apps (4.4%) or videos (1.9%). Assisting patients with steps toward cessation was infrequent. Few ob/gyns had discussions with patients immediately postpartum. Only 51.9% strongly agreed that they felt sufficiently informed about SHS/SIDS risks to educate their patients. The communication by ob/gyns of SHS/SIDS risk varies greatly and presents opportunities for improvement. Each additional minute spent having discussions and the use of supplemental materials, such as apps, may improve communication effectiveness. The discussion of smoking behaviors immediately postpartum may help to prevent smoker relapse. An increased awareness of statewide cessation resources by ob/gyns is needed to assist patients with cessation. The development of standardized risk messaging may reduce the variation in communication practices among ob/gyns.

Sudden Unexpected Infant Death: Review and Analysis of Adherence to Recommendations

Introduction Sudden Unexpected Infant Death (SUID) is a term that englobes the sudden and unexpected death of an infant less than 12 months, which can be explained by organic or traumatic causes, or that can't be explained such as cases of Sudden Infant Death Syndrome (SIDS). Although many risk factors have been associated with this syndrome, one of the most widely associated and studied are incorrect sleeping techniques and practices. In 2016, the American Academy of Pediatrics (AAP) updated their safe-sleeping guidelines and sleeping environment recommendations and strategies to prevent SIDS. Methods We conducted a cross-sectional study to analyze the sleeping environments in infants that attended both the inpatient and outpatient services at a public pediatric hospital in Mexico City. A 6-item questionnaire was applied to the parent or guardian to assess the sleeping habits of infants in their homes. Results A total of 184 infants were included in the study, with a mean age of 5.87 months. Overall, the number of parents that follow safe sleeping practices was very low, with no parents following all the AAP recommendations, and over 10% not following any. Although there is uncertainty about the pathogenesis of this syndrome, the focus has shifted to prevention, especially regarding the modifiable risk factors. Conclusions It was demonstrated that our population did not know about the proper and safe sleeping techniques. In the nearby future, our goal is for health authorities in our country to implement a strategy to make the AAP recommendations part of government health campaigns.

Bioelectrical impedance vector values in a Spanish healthy newborn population for nutritional assessment

INTRODUCTION

Vector bioimpedance analysis (BIVA) can be very useful for the evaluation of body composition, hydration, and nutritional status in infants and newborns. The objective of this study was to determine the impedance vector distribution for a group of healthy newborn Spanish children.

METHODS

This was a cross-sectional, descriptive study conducted with 154 healthy, Spanish newborns (gestational age: 37-41 weeks) aged 24 to 72 hours (79 males, 75 females). Weight, height, and cephalic-circumference were determined. Resistance and reactance were measured with a single-frequency impedance analyzer at 50 kHz (tetrapolar analysis). The newborns' specific 95% confidence intervals of the mean vectors and the 95%, 75%, and 50% tolerance intervals for the individual vector measurements were plotted using R and Xc components standardized by the subjects' lengths. The mean impedance vectors were compared with Hotelling's-T² test for vector analysis (significance level: P < .05).

RESULTS

The newborns exhibited gender-related differences in the mean impedance vector (mean [SD] R/H: 833.6 [97.5] Ohm/m in males vs 918.2 [107.7] Ohm/m in females; mean [SD] Xc/H: 91.3 [34.7] Ohm/m in males vs 95.6 [23.2] Ohm/m in females). No statistically significant differences in the mean impedance vectors were observed according to days of life. Lower values of resistance and slightly higher reactance values were observed in the healthy Spanish newborns compared to Italian newborns.

CONCLUSIONS

New tolerance ellipses were constructed for healthy Spanish newborns. These data allow detecting alterations in the hydration status and cell mass in term newborns in the first 3 days of life.

Population-based risks of mortality and preterm morbidity by gestational age and birth weight

OBJECTIVE

The objective of this study is to examine the effect of small or large for gestational age (SGA/LGA) status on mortality and morbidity by gestational age.

STUDY DESIGN

Logistic binomial regression was used to calculate relative risks (RRs) and 95% confidence intervals for infant mortality and preterm morbidities for SGA or LGA compared with appropriately grown (AGA) deliveries stratified by gestational age group.

RESULTS

Compared with AGA infants of similar gestational age, SGA infants were at increased risk for infant mortality. Mortality risk was decreased for LGA infants born between 25 and 27 weeks (RR: 0.6) but increased for LGA infants born between 28 and 31 weeks (RR: 1.9). Risk of preterm morbidity was increased for SGA infants born between 28 and 38 weeks, but decreased for LGA infants born before 37 weeks.

CONCLUSION

This study demonstrates the importance of considering birth weight for gestational age when evaluating morbidity and mortality risks.

Sudden Unexpected Death in Fetal Life Through Early Childhood

In March 2015, the Eunice Kennedy Shriver National Institute of Child Health and Human Development held a workshop entitled "Sudden Unexpected Death in Fetal Life Through Early Childhood: New Opportunities." Its objective was to advance efforts to understand and ultimately prevent sudden deaths in early life, by considering their pathogenesis as a potential continuum with some commonalities in biological origins or pathways. A second objective of this meeting was to highlight current issues surrounding the classification of sudden infant death syndrome (SIDS), and the implications of variations in the use of the term "SIDS" in forensic practice, and pediatric care and research. The proceedings reflected the most current knowledge and understanding of the origins and biology of vulnerability to sudden unexpected death, and its environmental triggers. Participants were encouraged to consider the application of new technologies and "omics" approaches to accelerate research. The major advances in delineating the intrinsic vulnerabilities to sudden death in early life have come from epidemiologic, neural, cardiac, metabolic, genetic, and physiologic research, with some commonalities among cases of unexplained stillbirth, SIDS, and sudden unexplained death in childhood observed. It was emphasized that investigations of sudden unexpected death are inconsistent, varying by jurisdiction, as are the education, certification practices, and experience of death certifiers. In addition, there is no practical consensus on the use of "SIDS" as a determination in cause of death. Major clinical, forensic, and scientific areas are identified for future research.

A Comparison of Birth Outcomes Among Black, Hispanic, and Black Hispanic Women

BACKGROUND

While non-Hispanic Black populations tend to be disproportionately affected by adverse reproductive outcomes, Hispanic populations tend to demonstrate healthier birth outcomes, regardless of socioeconomic background. Little is known about birth outcomes for women who are both Black and Hispanic. We examined whether birth outcomes and risk factors for women who are both Black and Hispanic most closely resemble those of women who are only Black or Hispanic and also compared these outcomes to those for Whites.

METHODS

Using the 2013 US natality files, we examined 2,970,315 singleton births to Black Hispanic, Hispanic, Black, and White mothers. We used logistic regression to calculate predicted probabilities of low birth weight (LBW), preterm birth (PTB), or small for gestational age (SGA). Race-stratified regression analysis was used to identify the factors that significantly predicted risk for each outcome for each racial/ethnic group.

RESULTS

Black mothers had the highest prevalence and predicted probabilities of experiencing all three outcomes. Black Hispanic mothers were less likely than Black mothers and more likely than Hispanic mothers to experience each of the adverse outcomes. We also found support for racial variation in risk and protective factors for mothers in the different groups. Factors like age and education inconsistently predicted risk of experiencing the birth outcomes for all groups. Overall, Black Hispanic mothers had birth outcomes and risk factor profiles like Hispanic mothers, although they had sociodemographic characteristics and health behaviors like Black mothers.

CONCLUSIONS

Patterning of birth outcomes among Black Hispanic women suggest an intersection of risk and protective factors associated with their respective racial and ethnic identities. Additional information about sociodemographic context is needed to develop a more complete picture of how factors related to race and ethnic group membership influence Black Hispanic women's birth outcomes.

The role of physiological studies and apnoea monitoring in infants

There is evidence that failure of cardio-respiratory control mechanisms plays a role in the final event of the Sudden Infant Death Syndrome (SIDS). Physiological studies during sleep in both healthy term born infants and those at increased risk for SIDS have been widely used to investigate how the major risk and protective factors for SIDS identified from epidemiological studies might alter infant physiology. Clinical polysomnography (PSG) in infants who eventually succumbed to SIDS however demonstrated abnormalities that were neither sufficiently distinctive nor predictive to support routine use of PSG for infants at risk for SIDS. PSG findings have also been shown to be not predictive of recurrence of Apparent Life Threatening Events (ALTE) and thus international guidelines state that PSG is not indicated for routine evaluation in infants with an uncomplicated ALTE, although PSG may be indicated when there is clinical evidence of a sleep related breathing disorder. A decision to undertake home apnoea monitoring should consider the potential advantages and disadvantages of monitoring for that individual, in the knowledge that there is no evidence of the efficacy of such devices in preventing SIDS.

Predictors of size for gestational age in St. Louis City and County

OBJECTIVE

To identify social, behavioral, and physiological risk factors associated with small for gestational age (SGA) by gestational age category in St. Louis City and County.

METHODS

A retrospective cohort study was conducted using birth certificate and fetal death records from 2000 to 2009 (n = 142,017). Adjusted associations of risk factors with SGA were explored using bivariate logistic regression. Four separate multivariable logistic regression analyses, stratified by gestational age, were conducted to estimate adjusted odds ratios.

RESULTS

Preeclampsia and inadequate weight gain contributed significantly to increased odds for SGA across all gestational age categories. The point estimates ranged from a 3.41 increased odds among women with preeclampsia and 1.76 for women with inadequate weight gain at 24-28 weeks' gestational age to 2.19 and 2.11 for full-term infants, respectively. Among full-term infants, smoking (aOR = 2.08), chronic hypertension (aOR = 1.46), and inadequate prenatal care (aOR = 1.25) had the next most robust and significant impact on SGA.

CONCLUSION

Preeclampsia and inadequate weight gain are significant risk factors for SGA, regardless of gestational age. Education on the importance of nutrition and adequate weight gain during pregnancy is vital. In this community, disparities in SGA and smoking rates are important considerations for interventions designed to improve birth outcomes.

Fetal growth and childhood acute lymphoblastic leukemia: findings from the childhood leukemia international consortium

Positive associations have been reported between the measures of accelerated fetal growth and risk of childhood acute lymphoblastic leukemia (ALL). We investigated this association by pooling individual-level data from 12 case-control studies participating in the Childhood Leukemia International Consortium. Two measures of fetal growth-weight-for-gestational-age and proportion of optimal birth weight (POBW)-were analysed. Study-specific odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, and combined in fixed effects meta-analyses. Pooled analyses of all data were also undertaken using multivariable logistic regression. Subgroup analyses were undertaken when possible. Data on weight for gestational age were available for 7,348 cases and 12,489 controls from all 12 studies and POBW data were available for 1,680 cases and 3,139 controls from three studies. The summary ORs from the meta-analyses were 1.24 (95% CI: 1.13, 1.36) for children who were large for gestational age relative to appropriate for gestational age, and 1.16 (95% CI: 1.09, 1.24) for a one-standard deviation increase in POBW. The pooled analyses produced similar results. The summary and pooled ORs for small-for-gestational-age children were 0.83 (95% CI: 0.75, 0.92) and 0.86 (95% CI: 0.77, 0.95), respectively. Results were consistent across subgroups defined by sex, ethnicity and immunophenotype, and when the analysis was restricted to children who did not have high birth weight. The evidence that accelerated fetal growth is associated with a modest increased risk of childhood ALL is strong and consistent with known biological mechanisms involving insulin-like growth factors. © 2013 UICC.

Smoking overrules many other risk factors for small for gestational age birth in less educated mothers

BACKGROUND

Although there is convincing evidence for the association between small for gestational age (SGA) and socioeconomic status (SES), it is not known to what extent explanatory factors contribute to this association.

AIM

To examine to what extent risk factors could explain educational inequalities in SGA.

STUDY DESIGN

In this study fully completed data were available for 3793 pregnant women of Dutch origin from a population-based cohort (ABCD study). Path-analysis was conducted to examine the role of explanatory factors in the relation of maternal education to SGA.

RESULTS

Low-educated pregnant women had a higher risk of SGA offspring compared to the high-educated women (OR 1.98, 95% CI 1.35-2.89). In path-analysis, maternal cigarette smoking and maternal height explained this association. Maternal age, hypertension, chronic disease, late entry into antenatal care, neighborhood income, underweight, environmental cigarette smoking, drug abuse, alcohol use, caffeine intake, fish intake, folic acid intake, anxiety, and depressive symptoms did not play a role in the association between maternal education and SGA birth.

CONCLUSION

Among a large array of potential factors, the elevated risk of SGA birth among low-educated women appeared largely attributable to maternal smoking and to a lesser extent to maternal height. To reduce educational inequalities more effort is required to include low-educated women especially in prenatal intervention programs such as smoking cessation programs instead of effort into reducing other SGA-risk factors, though these factors might still be relevant at the individual level.

Sociodemographic and meteorological correlates of sudden infant death in Taiwan

BACKGROUND

This study was designed, using three national datasets including the Taiwan Death Registry, Taiwan Birth Registry, and National Meteorological Dataset, to examine the sociodemographic, geographic and meteorological correlates of sudden infant death syndrome (SIDS).

METHODS

One thousand, six hundred and seventy-one cases of SIDS occurring between 1994 and 2003, and 8355 matched controls were included in this nested case-control study.

RESULTS

Over the study period, the annual rate of SIDS declined only slightly, with an average annual rate of 57.9/10(5) . Male infants (adjusted odds ratio [AOR], 1.19; 95% confidence interval [CI]: 1.06-1.33), preterm births (AOR, 1.69; 95%CI: 1.33-2.13), low birthweight (AOR, 2.87; 95%CI: 2.30-3.59), and birth order ≥3 (AOR, 1.62; 95%CI: 1.37-1.92) were the demographic risk factors for SIDS. Additionally, paternal age <25 years (AOR, 1.37; 95%CI: 1.09-1.71), urbanization (AOR, 1.46; 95%CI: 1.20-1.78), lower paternal education (elementary and less; AOR, 1.28; 95%CI: 1.01-1.64), and parental age difference >10 years (AOR, 1.72; 95%CI: 1.24-2.39) were also associated with increased risk of SIDS. It was also noted that daily average temperature ranging from 9.2°C to 14.2°C (AOR, 2.10; 95%CI: 1.67-2.64) was associated with the most increased risk, while temperature ≥26.4°C (AOR 0.60, 0.61) was significantly associated with the most reduced risk.

CONCLUSION

Sociodemographic, geographic and meteorological data can be used to identify families in greater need of early guidance and to promote various prevention measures to avoid the occurrence of SIDS.

Acute appendicitis and adverse pregnancy outcomes: a nationwide population-based study

BACKGROUND/OBJECTIVE

Acute appendicitis is the most common non-obstetric surgical procedure in pregnant women. Using two large-scale nationwide population-based datasets, this study aimed to assess the risk of adverse pregnancy outcomes between mothers with and without appendicitis in Taiwan.

METHODS

This study used two nationwide population-based datasets: the Taiwan National Health Insurance Research Dataset and the Taiwan national birth certificate registry. This study included 908 women who had live singleton births and who had been hospitalized with a diagnosis of acute appendicitis, and another randomly selected 4,540 women as a comparison group. Conditional logistic regression analyses were performed to calculate the risk of adverse pregnancy outcomes including low birth weight (LBW), preterm birth, small for gestational age (SGA), cesarean section (CS), congenital anomalies, Apgar scores at 5 min (<7), and pre-eclampsia/eclampsia.

RESULTS

The adjusted odds ratios for LBW, preterm birth, SGA, CS, and congenital anomalies in women with acute appendicitis were 1.82 (95 % CI = 1.43-2.30), 1.59 (95 % CI = 1.25-2.02), 1.33 (95 % CI = 1.12-1.60), 1.24 (95 % CI = 1.07-1.44), and 2.07 (95 % CI = 1.07-4.03), respectively, compared with women without acute appendicitis after adjusting for highest maternal educational level, marital status, geographic region, gestational diabetes, gestational hypertension, coronary heart disease, anemia, hyperlipidemia, obesity, and alcohol abuse/alcohol dependence syndrome, infant sex and parity, and paternal age.

CONCLUSIONS

There were increased risks for having LBW, preterm infants, SGA, congenital anomalies, and for experiencing CS among women with acute appendicitis than comparison women.

Birth weight for gestational age norms for a large cohort of infants born to HIV-negative women in Botswana compared with norms for U.S.-born black infants

Background

Standard values for birth weight by gestational age are not available for sub-Saharan Africa, but are needed to evaluate incidence and risk factors for intrauterine growth retardation in settings where HIV, antiretrovirals, and other in utero exposures may impact birth outcomes.

Methods

Birth weight data were collected from six hospitals in Botswana. Infants born to HIV-negative women between 26-44 weeks gestation were analyzed to construct birth weight for gestational age charts. These data were compared with published norms for black infants in the United States.

Results

During a 29 month period from 2007-2010, birth records were reviewed in real-time from 6 hospitals and clinics in Botswana. Of these, 11,753 live infants born to HIV-negative women were included in the analysis. The median gestational age at birth was 39 weeks (1^st quartile 38, 3^rd quartile 40 weeks), and the median birth weight was 3100 grams (1^st quartile 2800, 3^rd quartile 3400 grams). We constructed estimated percentile curves for birth weight by gestational age which demonstrate increasing slope during the third trimester and leveling off beyond 40 weeks. Compared with black infants in the United States, Botswana-born infants had lower median birth weight for gestational age from weeks 37 through 42 (p < .02).

Conclusions

We present birth weight for gestational age norms for Botswana, which are lower at term than norms for black infants in the United States. These findings suggest the importance of regional birth weight norms to identify and define risk factors for higher risk births. These data serve as a reference for Botswana, may apply to southern Africa, and may help to identify infants at risk for perinatal complications and inform comparisons among infants exposed to HIV and antiretrovirals in utero.

Aberrant fetal growth and early, late, and postneonatal mortality: an analysis of Milwaukee births, 1996-2007

OBJECTIVE

The objective of the study was to ascertain the association between fetal growth (small- [SGA], appropriate- [AGA], and large-for-gestational-age [LGA]) and early, late, and postneonatal mortality.

STUDY DESIGN

Birth certificate data for nonanomalous singletons, delivered from 1996 to 2007, were obtained for Milwaukee residents. Multivariate logistic regression analyses, adjusted for 19 covariates, determined the association between fetal growth and mortality.

RESULTS

Among the 123,383 live births, SGA was 57% higher than LGA (11% vs 7%). The infant mortality rate for SGA was 11.0, AGA, 5.3, and LGA, 2.7/1000 live births. SGA was a significant risk factor for early (adjusted odds ratio, 2.66) and late (2.06) but not postneonatal mortality. The adjusted risk of mortality for LGA was not significantly different from AGA. Over 12 years, 3 types of mortality for aberrant fetal growth did not change significantly.

CONCLUSION

In the city of Milwaukee, aberrant fetal growth was variably associated with early, late, and postneonatal mortality.

Fetal and maternal factors associated with infant mortality in vervet monkeys

BACKGROUND

Causes of infant death remain unknown in significant proportions of human and non-human primate pregnancies.

METHODS

A closed breeding colony with high rates of infant mortality had pregnancies assessed (n=153) by fetal measurements and maternal characteristics. Infant outcome was classified as neonatal death (stillborn or died <48 hours from birth), postnatal death (died 2-30 days) or surviving (alive after 30 days).

RESULTS

Fetal size did not predict outcome. Poor maternal glycemic control and low social ranking increased odds for adverse outcome (OR=3.72, P=0.01 and 2.27, P=0.04, respectively). Male sex was over-represented in stillbirths (P=0.04), and many were macrosomic, but size did not associate with maternal glycemic control measured as glycated hemoglobin A1c. Postnatally dead infants were smaller (P<0.01), which associated with behavioral factors and glycemic control.

CONCLUSIONS

Fetal growth estimates predicted gestational age but not fetal outcome. Maternal social status and metabolic health, particularly glycemic control, increased risks of adverse pregnancy outcome.

A meta-analysis of depression during pregnancy and the risk of preterm birth, low birth weight, and intrauterine growth restriction

CONTEXT

Maternal depressive symptoms during pregnancy have been reported in some, but not all, studies to be associated with an increased risk of preterm birth (PTB), low birth weight (LBW), and intrauterine growth restriction (IUGR).

OBJECTIVE

To estimate the risk of PTB, LBW, and IUGR associated with antenatal depression.

DATA SOURCES AND STUDY SELECTION

We searched for English-language and non-English-language articles via the MEDLINE, PsycINFO, CINAHL, Social Work Abstracts, Social Services Abstracts, and Dissertation Abstracts International databases (January 1980 through December 2009). We aimed to include prospective studies reporting data on antenatal depression and at least 1 adverse birth outcome: PTB (<37 weeks' gestation), LBW (<2500 g), or IUGR (<10th percentile for gestational age). Of 862 reviewed studies, 29 US-published and non-US-published studies met the selection criteria.

DATA EXTRACTION

Information was extracted on study characteristics, antenatal depression measurement, and other biopsychosocial risk factors and was reviewed twice to minimize error.

DATA SYNTHESIS

Pooled relative risks (RRs) for the effect of antenatal depression on each birth outcome were calculated using random-effects methods. In studies of PTB, LBW, and IUGR that used a categorical depression measure, pooled effect sizes were significantly larger (pooled RR [95% confidence interval] = 1.39 [1.19-1.61], 1.49 [1.25-1.77], and 1.45 [1.05-2.02], respectively) compared with studies that used a continuous depression measure (1.03 [1.00-1.06], 1.04 [0.99-1.09], and 1.02 [1.00-1.04], respectively). The estimates of risk for categorically defined antenatal depression and PTB and LBW remained significant when the trim-and-fill procedure was used to correct for publication bias. The risk of LBW associated with antenatal depression was significantly larger in developing countries (RR = 2.05; 95% confidence interval, 1.43-2.93) compared with the United States (RR = 1.10; 95% confidence interval, 1.01-1.21) or European social democracies (RR = 1.16; 95% confidence interval, 0.92-1.47). Categorically defined antenatal depression tended to be associated with an increased risk of PTB among women of lower socioeconomic status in the United States.

CONCLUSIONS

Women with depression during pregnancy are at increased risk for PTB and LBW, although the magnitude of the effect varies as a function of depression measurement, country location, and US socioeconomic status. An important implication of these findings is that antenatal depression should be identified through universal screening and treated.

Differences in birth weight for gestational age distributions according to the measures used to assign gestational age

Population-based standards for infant size for gestational age depend on accurate assessments of birth weight and gestational age; the accuracy of the latter measure has been questioned. The authors sought to explore how different methods of assigning gestational age in vital records data affect distributions of birth weight for gestational age. The 2005 US natality file was used to create 4 measures of gestational age for singleton births consisting of measures found on the 1989 (last menstrual period (LMP) and clinical estimate) and 2003 (LMP and obstetric estimate) revisions of the US standard birth certificate: clinical or obstetric estimate and LMP-based estimate agree within 7 days ("gold standard"); clinical estimate only; obstetric estimate only; and LMP-based estimate only. Birth weight for gestational age distributions differed according to the measurement of gestational age. Regardless of birth certificate revision, the median, 10th, and 90th percentile distributions were virtually identical for the gold standard, clinical estimate, and obstetric estimate. Birth weights for the LMP estimate were higher for preterm births and lower for postterm births for both birth certificate revisions. Agreement between the gold standard estimate and clinical and obstetric estimates of gestational age suggests that using the LMP-based estimate for establishing norms should be revisited.

Weight for gestational age affects the mortality of late preterm infants

BACKGROUND

Late preterm infant mortality is higher than that for term newborns. The association between weight for gestational age (WGA) category and late preterm mortality has not been well described.

OBJECTIVES

Our objectives for this research were as follows: (1) to compare neonatal and infant mortality rates of SGA, AGA, and LGA late preterm, early term, and term newborns; (2) to determine the relative risk of neonatal and infant death for each WGA category; and (3) to examine causes of neonatal and infant death.

METHODS

We reviewed linked birth and death certificate data for all infants from Utah born between 1999 and 2005 with a GA > or =34 weeks. We calculated neonatal and infant mortality rates for each GA/birth weight stratum and estimated mortality rate ratios using AGA term infants as the reference. International Classification of Diseases, Ninth Revision, codes were used to classify cause of death.

RESULTS

There were 343322 newborns with GA > or =34 weeks from 1999 to 2005. Late preterm SGA infants were approximately 44 times more likely than term AGA newborns to die in their first month and 22 times more likely to die in their first year. When infants dying from congenital conditions were excluded, the differences in mortality rate ratios persisted for SGA infants, especially those born in the late preterm period.

CONCLUSIONS

Being SGA substantially increases the already higher mortality of late preterm and early term newborns. This increased risk cannot be fully explained by an increased prevalence of lethal congenital conditions among SGA late preterm newborns. Clinicians caring for late preterm and early term newborns should be cognizant of their WGA category.

Apparent life-threatening events and sudden infant death syndrome: comparison of risk factors

OBJECTIVE

To compare the risk factors of 153 cases of apparent life-threatening event (ALTE) enrolled in the multicenter Collaborative Home Infant Monitoring Evaluation (CHIME) from 1994 to 1998 with the published risk factors for sudden infant death syndrome (SIDS).

STUDY DESIGN

Trained CHIME interviewers gathered histories of infants with ALTE who met the criteria. The following risk factors were analyzed: male predominance, gestational age, low birth weight, very low birth weight, incidence of small for gestational age (SGA), age at the event, multiparity, maternal age, and smoking. Population-based SIDS studies with >100 deaths, focusing on 1 or more pertinent risk factors and carried out during the decade in which CHIME data were collected, were chosen for comparison.

RESULTS

One of the 153 infants with ALTE in this study died during follow-up (0.6%). CHIME ALTE differed significantly from SIDS in 4 respects: fewer infants with low birth weight and SGA at birth, fewer teenage pregnancies, and a younger infant age at ALTE.

CONCLUSIONS

Although a number of risk factors for ALTE are similar to those for SIDS, the differences warrant a separate focus on ALTE beyond that on SIDS.

Small for gestational age infants and sudden infant death syndrome: a confluence of complex conditions

Perspective on the paper by Malloy (see page 473)