Small size for gestational age and the risk for infant mortality in the subsequent pregnancy

Trends in the incidence of fetal macrosomia and its phenotypes in the United States, 1971-2017

PURPOSE

Studies have reported a surge in the prevalence of obesity among various demographic groups including pregnant women in the U.S. Given the association between maternal obesity and risk of fetal macrosomia, we hypothesized that the incidence of fetal macrosomia will be on the rise in the U.S. We examined trends in fetal macrosomia and macrosomia phenotypes in the U.S. among singleton live births within the gestational age of 28-42 weeks inclusive.

METHODS

This was a retrospective cohort study covering the period 1971-2017 using U.S. Natality Data files. We applied Joinpoint regression models to derive the average annual percentage change in the outcome. We measured incidence and trends of fetal macrosomia which was defined as birth weight ≥ 4000 g. We further subdivided macrosomia into its phenotypes as previously recommended: Grade 1 (4000-4499 g), Grade 2 (4500-4999 g) and Grade 3 (≥ 5000 g).

RESULTS

A total of 147,331,305 singleton births over the entire study period of 47 years were analyzed. From a baseline incidence of 8.84%, the rate of fetal macrosomia declined to 8.07% by the end of the study representing a drop of 8.70% in relative terms. The greatest drop was among infants with Grade 3 macrosomia, the most severe and lethal phenotype. The most impactful factors were maternal age and gestational weight gain.

CONCLUSION

This study is the largest population-based study conducted regarding fetal macrosomia. The rate of fetal macrosomia declined over the previous 5 decades with the most substantial drop observed in the phenotype with the worst prognosis.

High birth weight and perinatal mortality among siblings: A register based study in Norway, 1967-2011

BACKGROUND

Perinatal mortality according to birth weight has an inverse J-pattern. Our aim was to estimate the influence of familial factors on this pattern, applying a cohort sibling design. We focused on excess mortality among macrosomic infants (>2 SD above the mean) and hypothesized that the birth weight-mortality association could be explained by confounding shared family factors. We also estimated how the participant's deviation from mean sibling birth weight influenced the association.

METHODS AND FINDINGS

We included 1 925 929 singletons, born term or post-term to mothers with more than one delivery 1967-2011 registered in the Medical Birth Registry of Norway. We examined z-score birth weight and perinatal mortality in random-effects and sibling fixed-effects logistic regression models including measured confounders (e.g. maternal diabetes) as well as unmeasured shared family confounders (through fixed effects models). Birth weight-specific mortality showed an inverse J-pattern, being lowest (2.0 per 1000) at reference weight (z-score +1 to +2) and increasing for higher weights. Mortality in the highest weight category was 15-fold higher than reference. This pattern changed little in multivariable models. Deviance from mean sibling birth weight modified the mortality pattern across the birth weight spectrum: small and medium-sized infants had increased mortality when being smaller than their siblings, and large-sized infants had an increased risk when outweighing their siblings. Maternal diabetes and birth weight acted in a synergistic fashion with mortality among macrosomic infants in diabetic pregnancies in excess of what would be expected for additive effects.

CONCLUSIONS

The inverse J-pattern between birth weight and mortality is not explained by measured confounders or unmeasured shared family factors. Infants are at particularly high mortality risk when their birth weight deviates substantially from their siblings. Sensitivity analysis suggests that characteristics related to maternal diabetes could be important in explaining the increased mortality among macrosomic infants.

Interconception Challenges of Women Who Had Prior Preterm Births

OBJECTIVE

To describe the interconception challenges of women who had prior preterm births.

DESIGN

We used a cross-sectional design and collected data via survey.

SETTING

King County, Washington.

PARTICIPANTS

Ninety-two women who had prior early preterm births (20-33 weeks gestation) were included.

METHODS

Women were recruited from a larger study focused on exploring the infectious pathways for early preterm birth. Participants were interviewed once using open-ended and close-ended surveys. The primary open-ended survey question was What are the five greatest challenges you experience now? We analyzed data using inductive and summative content analysis and descriptive statistics.

RESULTS

Ninety-one participants described challenges. One participant had no challenge. We categorized 11 challenges during the interconception period: Mothering (n = 70, 76%), Self-Care Desires (n = 35, 38%), Finances (n = 31, 34%), Employment (n = 31, 34%), Partner Relationships (n = 29, 32%), Individualized Concerns (n = 25, 27%), Mental Health (n = 23, 25%), Balance (n = 22, 24%), Physical Health (n = 19, 21%), Housing (n = 18, 20%), and Family (n = 17, 19%).

CONCLUSION

Participants described an array of challenges that often related to their roles as mothers, employees, and partners. Our research advances knowledge by describing contemporary challenges of women during the interconception period.

Cluster Randomized Controlled Trial of Group Prenatal Care: Perinatal Outcomes Among Adolescents in New York City Health Centers

OBJECTIVES

We compared an evidence-based model of group prenatal care to traditional individual prenatal care on birth, neonatal, and reproductive health outcomes.

METHODS

We performed a multisite cluster randomized controlled trial in 14 health centers in New York City (2008-2012). We analyzed 1148 pregnant women aged 14 to 21 years, at less than 24 weeks of gestation, and not at high obstetrical risk. We assessed outcomes via medical records and surveys.

RESULTS

In intention-to-treat analyses, women at intervention sites were significantly less likely to have infants small for gestational age (< 10th percentile; 11.0% vs 15.8%; odds ratio = 0.66; 95% confidence interval = 0.44, 0.99). In as-treated analyses, women with more group visits had better outcomes, including small for gestational age, gestational age, birth weight, days in neonatal intensive care unit, rapid repeat pregnancy, condom use, and unprotected sex (P = .030 to < .001). There were no associated risks.

CONCLUSIONS

CenteringPregnancy Plus group prenatal care resulted in more favorable birth, neonatal, and reproductive outcomes. Successful translation of clinical innovations to enhance care, improve outcomes, and reduce cost requires strategies that facilitate patient adherence and support organizational change.

The effect of mother's age and other related factors on neonatal survival associated with first and second birth in rural, Tanzania: evidence from Ifakara health and demographic surveillance system in rural Tanzania

BACKGROUND

With a view to improve neonatal survival, data on birth outcomes are critical for planning maternal and child health care services. We present information on neonatal survival from Ifakara Health and Demographic Surveillance System (HDSS) in Tanzania, regarding the influence of mother's age and other related factors on neonatal survival of first and second births.

METHODS

The study conducted analysis using longitudinal health and demographic data collected from Ifakara HDSS in parts of Kilombero and Ulanga districts in Morogoro region. The analysis included first and second live births that occurred within six years (2004-2009) and the unit of observation was a live birth. A logistic regression model was used to assess the influence of socio-demographic factors on neonates' survival.

RESULTS

A total of 18,139 first and second live births were analyzed. We found neonatal mortality rate of 32 per 1000 live births (95% CI: 29/1000-34/1000). Results from logistic regression model indicated increase in risk of neonatal mortality among neonates those born to young mothers aged 13-19 years compared with those whose mother's aged 20-34 years (aOR = 1.64, 95% CI = 1.34-2.02). We also found that neonates in second birth order were more likely to die than those in first birth order (aOR = 1.85: 95% CI = 1.52-2.26). The risk of neonatal mortality among offspring of women who had a partner co-resident was 18% times lower as compared with offspring of mothers without a partner co-resident in the household (aOR = 0.82: 95% CI = 0.66-0.98). Short birth interval (<33 months) was associated with increased risk of neonatal mortality (aOR = 1.50, 95% CI =1.16-1.96) compared with long birth interval (> = 33 months). Male born neonates were found to have an increased risk (aOR = 1.34, 95% CI =1.13- 1.58) of neonatal mortality as compared to their female counterparts.

CONCLUSIONS

Delaying the age at first birth may be a valuable strategy to promote and improve neonatal health and survival. Moreover, birth order, birth interval, mother's partner co-residence and sex of the neonate appeared as important markers for neonatal survival.

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.