Risk and Protective Factors for Preterm Birth Among Racial, Ethnic, and Socioeconomic Groups in California.

Importance: Preterm birth (PTB) (gestational age <37 weeks) is a major cause of infant mortality and morbidity in the US and is marked by racial and ethnic and socioeconomic inequities. Further research is needed to elucidate the association of risk and protective factors with trends in PTB rates and with related inequities. Objective: To describe the association of PTB rates with inequities as well as related risk and protective factors over the past decade in a US population-based cohort. Design, Setting, and Participants: This retrospective cohort study of singleton live births in California from January 1, 2011, to December 31, 2022, was conducted using vital statistics records and hospital records. The cohort included births with a gestational age of 22 to 44 weeks. Main Outcomes and Measures: Preterm birth rates by racial and ethnic group and by public and nonpublic insurance (considered as a proxy for socioeconomic status) were studied across years. Log-linear regression (relative risks with 95% CIs) was used to evaluate risk and protective factors within groups. Associations of PTB rates with risk and protective factors were assessed. Results: This study included 5 431 018 singleton live births to individuals who identified as American Indian or Alaska Native (0.3%), Asian (14.2%), Black (4.9%), Hispanic (47.8%), or White (27.0%). A total of 43.1% of births were to individuals with public health insurance. From 2011 to 2022, the overall PTB rate increased from 6.8% to 7.5% (change [SE], 10.6% [0.6%]; z score of 18.5; P < .001). Differences in PTB rates and associated changes were observed for racial and ethnic groups and insurance groups. For example, 2022 PTB rates ranged from 5.8% among White individuals with nonpublic insurance to 11.3% among Black individuals with public health insurance. From 2011 to 2022, PTB rates decreased from 9.1% to 8.8% (change [SE], -3.5% [4.2]; z score of -0.8; P = .42) among Black individuals with nonpublic insurance, whereas they increased from 6.4% to 9.5% (change [SE], 49.8% [16.0%]; z score of 3.1; P = .002) among American Indian or Alaska Native individuals with nonpublic insurance. Increases in some risk factors (eg, preexisting diabetes, sexually transmitted infections, mental health conditions) were observed in most groups, and decreases in some protective factors (eg, participation in the California Women, Infants, and Children program) (P for trend < .001 from 2011 to 2021) were observed mostly in low-income groups. Conclusions and Relevance: In this cohort study of singleton live births in California, PTB rates increased in many groups. Persistent racial and ethnic and socioeconomic inequities were also observed. Changes in risk and protective factors provided clues to patterns of PTB. These data point to an urgent need to address factors associated with PTB at both the individual and population levels.

Early Newborn Metabolic Patterning and Sudden Infant Death Syndrome.

Importance: Sudden infant death syndrome (SIDS) is a major cause of infant death in the US. Previous research suggests that inborn errors of metabolism may contribute to SIDS, yet the relationship between SIDS and biomarkers of metabolism remains unclear. Objective: To evaluate and model the association between routinely measured newborn metabolic markers and SIDS in combination with established risk factors for SIDS. Design, Setting, and Participants: This was a case-control study nested within a retrospective cohort using data from the California Office of Statewide Health Planning and Development and the California Department of Public Health. The study population included infants born in California between 2005 and 2011 with full metabolic data collected as part of routine newborn screening (NBS). SIDS cases were matched to controls at a ratio of 1:4 by gestational age and birth weight z score. Matched data were split into training (2/3) and testing (1/3) subsets. Data were analyzed from January 2005 to December 2011. Exposures: Metabolites measured by NBS and established risk factors for SIDS. Main Outcomes and Measures: The primary outcome was SIDS. Logistic regression was used to evaluate the association between metabolic markers combined with known risk factors and SIDS. Results: Of 2 276 578 eligible infants, 354 SIDS (0.016%) cases (mean [SD] gestational age, 38.3 [2.3] weeks; 220 male [62.1%]) and 1416 controls (mean [SD] gestational age, 38.3 [2.3] weeks; 723 male [51.1%]) were identified. In multivariable analysis, 14 NBS metabolites were significantly associated with SIDS in a univariate analysis: 17-hydroxyprogesterone, alanine, methionine, proline, tyrosine, valine, free carnitine, acetyl-L-carnitine, malonyl carnitine, glutarylcarnitine, lauroyl-L-carnitine, dodecenoylcarnitine, 3-hydroxytetradecanoylcarnitine, and linoleoylcarnitine. The area under the receiver operating characteristic curve for a 14-marker SIDS model, which included 8 metabolites, was 0.75 (95% CI, 0.72-0.79) in the training set and was 0.70 (95% CI, 0.65-0.76) in the test set. Of 32 infants in the test set with model-predicted probability greater than 0.5, a total of 20 (62.5%) had SIDS. These infants had 14.4 times the odds (95% CI, 6.0-34.5) of having SIDS compared with those with a model-predicted probability less than 0.1. Conclusions and Relevance: Results from this case-control study showed an association between aberrant metabolic analytes at birth and SIDS. These findings suggest that we may be able to identify infants at increased risk for SIDS soon after birth, which could inform further mechanistic research and clinical efforts focused on monitoring and prevention.

Trends and adverse pregnancy and birth outcomes associated with stimulant-related disorder diagnosis.

BACKGROUND AND AIMS: Stimulant-related disorders (SRD), or the continued misuse of illicit or prescribed stimulants, during pregnancy can have adverse health effects for mothers and infants. This study aimed to measure prevalence and trends of SRD diagnosis in pregnancy, and associations between SRD diagnosis and adverse maternal and infant health outcomes, among pregnant individuals in California. DESIGN: Retrospective cohort study. SETTING: California, USA. PARTICIPANTS: Pregnant individuals from the Study of Outcomes in Mothers and Infants (SOMI) with singleton live births between 2012 and 2020 (n = 3 740 079). MEASUREMENTS: SRD diagnosis (excluding cocaine) and maternal (gestational diabetes, gestational hypertension [gHTN], severe maternal morbidity [SMM]) and infant (very preterm birth [gestational age <32 weeks], preterm birth [gestational age 32-37 weeks], neonatal intensive care unit [NICU] admission, small for gestational age [SGA]) outcomes were classified using International Classification of Disease (ICD) codes and vital statistics. Risk ratios were estimated with modified Poisson log linear regression that accounted for sibling pregnancies. Covariates included maternal sociodemographic characteristics, mental and physical health problems, nicotine use and co-occurrence of other diagnosed substance use disorders. Bias analyses were conducted to address unmeasured confounding and exposure misclassification. FINDINGS: SRD diagnosis among pregnant individuals increased from 2012 to 2020 (554 to 748 per 100 000 births). SRD diagnosis was associated with an increased risk of SMM (adjusted risk ratio [aRR] = 2.3; 95% confidence interval [CI] = 2.2-2.5), gHTN (aRR = 1.8; 95% CI = 1.7-1.9), very preterm birth (aRR = 2.2, 95% CI = 2.0-2.5), preterm birth (aRR = 2.1, 95% CI = 2.1-2.2) and NICU admission (aRR = 2.0, 95%CI = 1.9-2.0), and a decreased risk of gestational diabetes (aRR = 0.8; 95% CI = 0.8-0.9). SRD diagnosis was not associated with infants born SGA. Findings were generally robust to unmeasured confounding and misclassification of diagnosis. CONCLUSIONS: Stimulant-related disorder diagnosis during pregnancy appears to be associated with an increased risk for select adverse maternal and infant health outcomes including severe maternal morbidity, gestational hypertension, very preterm birth, preterm birth and neonatal intensive care unit admission.

Birth defects among offspring of California firefighters, 2007-2019.

PURPOSE: Limited research examines birth defects from maternal or paternal firefighting exposure. This study aims to assess if maternal or paternal occupational exposure to firefighting during periconception is associated with offspring birth defects. METHODS: Data from California birth certificates (2007-2019) were linked to maternal / offspring hospitalization records. Occupation during the periconceptional period was categorized from vital statistics as the following: paternal non-firefighting (n = 4,135,849), paternal firefighting (n = 22,732), maternal non-firefighting (n = 3,332,255) and maternal firefighting (n = 502). Birth defects were identified using ICD codes, grouped by anatomical regions. Adjusted odds ratios were estimated, and sensitivity analyses explored police officer reference groups and detailed birth defect categories. RESULTS: Offspring of paternal firefighters had lower odds of circulatory defects (aOR = 0.9, 95% CI 0.8, 1.0), oral clefts (aOR = 0.6, 95% CI 0.4, 0.8) and respiratory defects (0.7, 95% CI 0.6, 0.9) compared to paternal non-firefighters. Associations between maternal firefighting and offspring birth defects were imprecise. Substituting police officers as the reference group attenuated findings. CONCLUSIONS: Offspring of paternal firefighters may have similar or slightly lower birth defect odds compared to offspring of non-firefighters. Limited data was available for assessing maternal firefighting outcomes. Future studies should prioritize studies using occupational exposure matrices to limit misclassification of exposure.

Cardiovascular Events During Pregnancy: Implications for Adverse Pregnancy Outcomes in Individuals With Autoimmune and Rheumatic Diseases.

OBJECTIVE: This study examined maternal cardiovascular (CV) events relative to adverse pregnancy outcomes among individuals with autoimmune rheumatic diseases (ARDs), primary antiphospholipid syndrome (APS), and those with neither. METHODS: Using a California population-based birth cohort (2005-2020), we identified those with CV events (CVEs), ARDs, and APS through International Classification of Diseases, 9th and 10th revisions, Clinical Modification codes in maternal discharge records. Selected adverse pregnancy outcomes identified from birth certificates were preterm birth (PTB; < 37 weeks' gestation), small-for-gestational-age infants (SGA; birth weight < 10th percentile for age and sex), and a composite of either outcome. Adjusted risk ratios (aRRs) for adverse outcomes and their 95% CIs were calculated. RESULTS: CVEs occurred more frequently in individuals with ARDs (265 of 19,340 [1.4%]) and primary APS (428 of 7758 [5.5%]) than those without (17,130 of 7,004,334 [0.3%]). The presence vs absence of CVEs was associated with a greater incidence of adverse outcomes in ARD (53.2% vs 26.6%), APS (30.6% vs 20.7%), and non-ARD/APS pregnancies (28.2% vs 15.2%). CVEs were associated with increased risks of SGA in all groups (aRRs 1.2-1.5) and PTB in ARD (aRR 1.6, 95% CI 1.3-2.0) and non-ARD/APS (aRR 1.7, 95% CI 1.7-1.8) pregnancies. CONCLUSION: CVEs were associated with modestly increased risks (20-70%) for PTB, SGA, or both across the groups. Notably, > 50% of ARD pregnancies with CVEs experienced adverse pregnancy outcomes. Given that ARD and APS pregnancies have higher (although still low) rates of CVEs and have higher baseline risks of adverse pregnancy outcomes than the general population, the additional burden conferred by CVEs is clinically important.

Risk of Adverse Perinatal Outcomes Among African-born Black Women in California, 2011-2020.

BACKGROUND: African-born women have a lower risk of preterm birth and small for gestational age (SGA) birth compared with United States-born Black women, however variation by country of origin is overlooked. Additionally, the extent that nativity disparities in adverse perinatal outcomes to Black women are explained by individual-level factors remains unclear. METHODS: We conducted a population-based study of nonanomalous singleton live births to United States- and African-born Black women in California from 2011 to 2020 (n = 194,320). We used age-adjusted Poisson regression models to estimate the risk of preterm birth and SGA and reported risk ratios (RR) and 95% confidence intervals (CI). Decomposition using Monte Carlo integration of the g-formula computed the percentage of disparities in adverse outcomes between United States- and African-born women explained by individual-level factors. RESULTS: Eritrean women (RR = 0.4; 95% CI = 0.3, 0.5) had the largest differences in risk of preterm birth and Cameroonian women (RR = 0.5; 95% CI = 0.3, 0.6) in SGA birth, compared with United States-born Black women. Ghanaian women had smaller differences in risk of preterm birth (RR = 0.8; 95% CI = 0.7, 1.0) and SGA (RR = 0.9; 95% CI = 0.8, 1.1) compared with United States-born women. Overall, we estimate that absolute differences in socio-demographic and clinical factors contributed to 32% of nativity-based disparities in the risk of preterm birth and 26% of disparities in SGA. CONCLUSIONS: We observed heterogeneity in risk of adverse perinatal outcomes for African- compared with United States-born Black women, suggesting that nativity disparities in adverse perinatal outcomes were not fully explained by differences in individual-level factors.

Prenatal cannabis use disorder and gastroschisis in California, 2007-19.

BACKGROUND: Gastroschisis is a congenital anomaly of the abdominal wall with an unknown aetiology. Recent trends in the prevalence of gastroschisis suggest that changing environmental or behavioural factors may contribute. We examined whether prenatal cannabis use disorder was associated with gastroschisis. METHODS: The Study of Outcomes of Mothers and Infants is a population-based cohort compiled of California birth records that have been linked to Department of Health Care Access and Information hospitalization, emergency department and ambulatory surgery records. We included 2007-19 singleton live births (n = 5 774 656). Cannabis use disorder was measured by diagnosis codes at any visit during pregnancy or at birth. Gastroschisis was measured by diagnosis or surgical repair procedure codes at birth or during the first year of life. RESULTS: The prevalence of cannabis use disorder was about 1%. The prevalence of gastroschisis was 0.14% and 0.06% among those with and without cannabis use disorder, respectively. There were positive associations between cannabis use disorder and gastroschisis when using a multivariable model [adjusted risk ratio (aRR) = 1.3, 95% confidence interval (CI) 1.0, 1.7) and a matched sample approach (aRR = 1.5, 95% CI 1.1, 2.1). The association varied by maternal age and was largest among people aged >34 years (aRR = 2.5, 95% CI 1.0, 5.8). CONCLUSIONS: We confirm findings of a positive association between cannabis exposure and gastroschisis and add that it is strongest when maternal age is greater than 34 years. More investigation into whether the association is causal, and why the association varies by maternal age, is encouraged.

Impact of being underweight before pregnancy on preterm birth by race/ethnicity and insurance status in California: an analysis of birth records.

BACKGROUND: The US still has a high burden of preterm birth (PTB), with important disparities by race/ethnicity and poverty status. There is a large body of literature looking at the impact of pre-pregnancy obesity on PTB, but fewer studies have explored the association between underweight status on PTB, especially with a lens toward health disparities. Furthermore, little is known about how weight, specifically pre-pregnancy underweight status, and socio-economic-demographic factors such as race/ethnicity and insurance status, interact with each other to contribute to risks of PTB. OBJECTIVES: The objective of this study was to measure the association between pre-pregnancy underweight and PTB and small for gestational age (SGA) among a large sample of births in the US. Our secondary objective was to see if underweight status and two markers of health disparities - race/ethnicity and insurance status (public vs. other) - on PTB. STUDY DESIGN: We used data from all births in California from 2011 to 2017, which resulted in 3,070,241 singleton births with linked hospital discharge records. We ran regression models to estimate the relative risk of PTB by underweight status, by race/ethnicity, and by poverty (Medi-cal status). We then looked at the interaction between underweight status and race/ethnicity and underweight and poverty on PTB. RESULTS: Black and Asian women were more likely to be underweight (aRR = 1.0, 95% CI: 1.01, 1.1 and aRR = 1.4, 95% CI: 1.4, 1.5, respectively), and Latina women were less likely to be underweight (aRR = 0.7, 95% CI: 0.7, 0.7). Being underweight was associated with increased odds of PTB (aRR = 1.3, 95% CI 1.3-1.3) and, after controlling for underweight, all nonwhite race/ethnic groups had increased odds of PTB compared to white women. In interaction models, the combined effect of being both underweight and Black, Indigenous and People of Color (BIPOC) statistically significantly reduced the relative risk of PTB (aRR = 0.9, 95% CI: 0.8, 0.9) and SGA (aRR = 1.0, 95% CI: 0.9, 1.0). The combined effect of being both underweight and on public insurance increased the relative risk of PTB (aRR = 1.1, 95% CI: 1.1, 1.2) but there was no additional effect of being both underweight and on public insurance on SGA (aRR = 1.0, 95% CI: 1.0, 1.0). CONCLUSIONS: We confirm and build upon previous findings that being underweight preconception is associated with increased risk of PTB and SGA - a fact often overlooked in the focus on overweight and adverse birth outcomes. Additionally, our findings suggest that the effect of being underweight on PTB and SGA differs by race/ethnicity and by insurance status, emphasizing that other factors related to inequities in access to health care and poverty are contributing to disparities in PTB.

Racial and Ethnic Inequities in Therapeutic Hypothermia and Neonatal Hypoxic-Ischemic Encephalopathy: A Retrospective Cohort Study.

OBJECTIVE: To investigate racial inequities in the use of therapeutic hypothermia (TH) and outcomes in infants with hypoxic-ischemic encephalopathy (HIE). STUDY DESIGN: We queried an administrative birth cohort of mother-baby pairs in California from 2010 through 2019 using International Classification of Diseases codes to evaluate the association between race and ethnicity and the application of TH in infants with HIE. We identified 4779 infants with HIE. Log-linear regression was used to calculate risk ratios (RR) for TH, adjusting for hospital transfer, rural location, gestational age between 35 and 37 weeks, and HIE severity. Risk of adverse infant outcome was calculated by race and ethnicity and stratified by TH. RESULTS: From our identified cohort, 1338 (28.0%) neonates underwent TH. White infants were used as the reference sample, and 410 (28.4%) received TH. Black infants were significantly less likely to receive TH with 74 (20.0%) with an adjusted risk ratio (aRR) of 0.7 (95% CI 0.5-0.9). Black infants with any HIE who did not receive TH were more likely to have a hospital readmission (aRR 1.36, 95% CI 1.10-1.68) and a tracheostomy (aRR 3.07, 95% CI 1.19-7.97). Black infants with moderate/severe HIE who did not receive TH were more likely to have cerebral palsy (aRR 2.72, 95% CI 1.07-6.91). CONCLUSIONS: In this study cohort, Black infants with HIE were significantly less likely to receive TH. Black infants also had significantly increased risk of some adverse outcomes of HIE. Possible reasons for this inequity include systemic barriers to care and systemic bias.

Disparities in the impact of heat wave definitions on emergency department visits during the first year of life among preterm and full-term infants in California.

INTRODUCTION: Heat waves will be aggravated due to climate change, making this a critical public health threat. However, heat wave definitions to activate alert systems can be ambiguous, highlighting the need to assess a range of definitions to identify those that contribute to the most adverse health outcomes. Additionally, children are highly susceptible to the impacts of heat waves, especially infants, despite the lack of focus on this subpopulation. We aimed to assess the relationship between 30 heat wave definitions and the first all-cause emergency department (ED) visits for California infants. We also examined modification of this relationship by preterm birth status and demographic characteristics to identify possible health disparities. METHODS: Live-born, singleton deliveries from the Study of Outcomes in Mothers and Infants born in 2014-2018 were included. Thirty heat wave definitions were assessed based on temperature metrics (minimum/maximum temperatures), thresholds (90th; 92.5th; 95th; 97.5th; 99th percentiles), and duration (1-; 2-; 3-days). A time-stratified case-crossover design assessed heat wave impacts on ED visits using infants with a warm season ED visit (May-October) within the first year of life (n = 228,250). Effect modification by preterm birth status, age, sex, race/ethnicity, education, and delivery payment type was also investigated. RESULTS: Infants demonstrated increased risk of an ED visit with exposure to all heat definitions. The 3-day minimum temperature 99th percentile definition had the highest adjusted odds ratio (AOR: 1.14; 95% CI: 1.05-1.23) for the total population. Term infants were more affected by some heat waves than preterm infants. Effect modification was additionally identified, such as by maternal education. DISCUSSION: This study provides insight on the heat wave definitions that lead to adverse health outcomes and the identification of the most susceptible infants to these impacts, which has implications on heat-related interventions.

Pregnancy characteristics and outcomes among birthing individuals with a diagnosis of fetal alcohol syndrome.

BACKGROUND: Fetal alcohol syndrome (FAS) can have adverse effects on health outcomes throughout the life course. Adults with FAS have an increased risk of chronic and infectious diseases. Although these conditions can affect reproductive health, few have described perinatal outcomes among individuals with an FAS diagnosis. METHODS: We analyzed data from the Study of Mothers and Infants, an administrative birth cohort derived from California birth certificates linked with a hospital discharge database. The cohort consisted of 7.3 million singleton, live births between 2005 and 2021. FAS was identified by International Classification of Diseases (ICD) codes in maternal hospital discharge records. Pregnancy and birth outcomes were captured via ICD codes in maternal or infant records. We performed descriptive analyses for pregnancy and birth outcomes by maternal FAS diagnosis. RESULTS: There were 35 babies born to 30 individuals with an FAS diagnosis between 2005 and 2021 (0.5/100,000 live births). The prevalence of births to individuals with an FAS diagnosis increased over the period. Individuals with an FAS diagnosis were more likely to identify as non-Hispanic White, or "other/multiple" race, and less likely to be Hispanic than those without FAS. They were also more likely to be publicly insured and less than 18 years old. Birthing individuals with FAS were also more likely to use nicotine during pregnancy and to have diagnoses of mental health disorders, epilepsy, substance use disorders, preexisting or gestational hypertension, and sexually transmitted infections or other infections complicating pregnancy. Infants of individuals with FAS were more likely to be born prematurely or small for gestational age and be admitted to the neonatal intensive care unit. CONCLUSIONS: These findings highlight the need for improved recognition of FAS among birthing people. The results suggest that individuals with FAS would benefit from early and sustained medical care prior to pregnancy to optimize perinatal outcomes.

What drives outcomes in infants of mothers with congenital heart disease? A mediation analysis.

OBJECTIVE: Infants of mothers with adult congenital heart disease (ACHD) are at increased risk for adverse pregnancy and neonatal outcomes. We aim to identify mediators in the relationship between ACHD and pregnancy and infant outcomes. STUDY DESIGN: Case-control study using linked maternal and infant hospital records. Structural equation modeling was performed to assess for potential mediators of pregnancy and infant outcomes. RESULT: We showed an increased risk of multiple adverse infant and pregnancy outcomes among infants born to mothers with ACHD. Maternal placental syndrome and congestive heart failure were mediators of prematurity. Prematurity and critical congenital heart disease in the infant were mediators of infant outcomes. However, the direct effect of ACHD on outcomes beyond that explained by these mediators remained significant. CONCLUSION: While significant mediators of infant and pregnancy outcomes were identified, there was a large direct effect of maternal ACHD. Further studies should aim to identify more factors that explain these infants' vulnerability.

Racial Disparities in Cesarean Delivery Rates: Do Hospital-Level Factors Matter?

OBJECTIVE: This study aimed to assess whether racial disparities in nulliparous, term, singleton, vertex cesarean delivery rates vary among hospitals of different type (academic vs. nonacademic), setting (urban vs. rural), delivery volume, and patient population. STUDY DESIGN: This is a retrospective cohort study including singleton term vertex live births in nulliparous Black and non-Hispanic White birthing people in California between 2011 and 2017. Cesarean delivery rates were obtained using birth certificate data and International Classification of Diseases, 9th/10th Revision codes. Risk of cesarean delivery was compared among Black versus White birthing people by hospital type (academic, nonacademic), setting (rural, suburban, urban), volume (< 1,200, 1,200-2,300, 2,400-3,599, ≥3,600 deliveries annually), and patient population (proportion Black-serving). Federal Information Processing codes were used to designate hospital setting. Risks were calculated using univariable and multivariable logistic regression and adjusted for birthing person age, body mass index, medical comorbidities, gestational age, labor type (spontaneous vs. induction), and infant birthweight. RESULTS: The sample included 59,441 Black (cesarean delivery rate: 30.2%) and 363,624 White birthing people (cesarean delivery rate: 26.1%). Black birthing people were significantly more likely than White birthing people to have a cesarean delivery across nearly all hospital-level factors considered with adjusted relative risks ranging from 1.1 to 1.3. The only exception was rural settings in which the adjusted relative risk was 1.3 but did not reach statistical significance. CONCLUSION: Black-White disparities in nulliparous, term, singleton, vertex cesarean delivery rates were persistent across all hospital-level factors we considered: academic status, rurality, delivery volume, and patient population. Furthermore, disparities existed at roughly the same magnitude regardless of hospital characteristics. These global increased risks likely reflect structural inequities in care, which contribute to disparities in pregnancy-related morbidity and mortality. These data should encourage providers, hospital systems, and quality collaboratives to further investigate racial disparities in cesarean delivery rates and develop strategies for eliminating them. KEY POINTS: · Nulliparous Black birthing people are more likely than White to undergo cesarean delivery.. · This persists across hospitals of all academic status, rurality, delivery volume, and patient population.. · These findings likely reflect structural rather than institutional inequities in obstetric care..

Resuscitation, survival and morbidity of extremely preterm infants in California 2011-2019.

OBJECTIVE: To describe changes over time in resuscitation, survival, and morbidity of extremely preterm infants in California. STUDY DESIGN: This population-based, retrospective cohort study includes infants born ≤28 weeks. Linked birth certificates and hospital discharge records were used to evaluate active resuscitation, survival, and morbidity across two epochs (2011-2014, 2015-2019). RESULTS: Of liveborn infants, 0.6% were born ≤28 weeks. Active resuscitation increased from 16.9% of 22-week infants to 98.1% of 25-week infants and increased over time in 22-, 23-, and 25-week infants (p-value ≤ 0.01). Among resuscitated infants, survival to discharge increased from 33.2% at 22 weeks to 96.1% at 28 weeks. Survival without major morbidity improved over time for 28-week infants (p-value < 0.01). CONCLUSION: Among infants ≤28 weeks, resuscitation and survival increased with gestational age and morbidity decreased. Over time, active resuscitation of periviable infants and morbidity-free survival of 28-week infants increased. These trends may inform counseling around extremely preterm birth.

Maternal Mental Health Diagnoses and Infant Emergency Department Use, Hospitalizations, and Death.

BACKGROUND: The period surrounding childbirth is a uniquely vulnerable time for women and their mental health. We sought to describe the association between maternal mental health diagnoses in the year prior and after birth and infant Emergency Department (ED) utilization, hospitalization, and death. METHODS: We studied mothers who gave singleton live birth in California (2011-2017) and their infants using linked infant birth and death certificates and maternal and infant discharge records. Maternal mental health diagnoses in the year before and after birth were identified using International Classification of Diseases (ICD) codes. We abstracted infant ED visits, hospitalizations, discharge diagnoses, deaths, and causes of death. Log-linear regression was used to compare relative risks of infant outcomes between mothers with and without mental health diagnoses, adjusting for maternal variables. RESULTS: Of the 3,067,069 mother-infant pairs, 85,047 (2.8%) mothers had at least one mental health diagnosis in the year before and after birth. Infants of mothers with mental health diagnoses were more likely to visit the ED (aRR 1.2, CI:1.1-1.2), have three or more ED visits (aRR 1.4, CI:1.3-1.4), be hospitalized (aRR 1.1, CI:1.04-1.1), and die (aRR 1.7, CI:1.6-1.8) in the first year of life. These infants were also more likely to be diagnosed with accidental injuries, nonaccidental trauma, and non-specific descriptive diagnosis (fussiness/fatigue/brief resolved unexplained event). CONCLUSION: This large administrative cohort study showed associations between maternal mental health diagnoses and infant acute ED visits, hospitalization, and death. This study underscores the urgent need to understand what is driving these findings and how to mitigate this risk.

Structural racism, nativity and risk of adverse perinatal outcomes among Black women.

BACKGROUND: Black women in the United States (US) have the highest risk of preterm birth (PTB) and small for gestational age (SGA) births, compared to women of other racial groups. Among Black women, there are disparities by nativity whereby foreign-born women have a lower risk of PTB and SGA compared to US-born women. Differential exposure to racism may confer nativity-based differences in adverse perinatal outcomes between US- and foreign-born Black women. This remains unexplored among US- and African-born women in California. OBJECTIVES: Evaluate the relationship between structural racism, nativity, PTB and SGA among US- and African-born Black women in California. METHODS: We conducted a population-based study of singleton births to US- and African-born Black women in California from 2011 to 2017 (n = 131,424). We examined the risk of PTB and SGA by nativity and neighbourhoods with differing levels of structural racism, as measured by the Index of Concentration at the Extremes. We fit crude and age-adjusted Poisson regression models, estimated using generalized estimating equations, with risk ratios (RR) and 95% confidence intervals (CI) as the effect measure. RESULTS: The proportions of PTB and SGA were 9.7% and 14.5%, respectively, for US-born women, while 5.6% and 8.3% for African-born women. US-born women (n = 24,782; 20.8%) were more likely to live in neighbourhoods with high structural racism compared to African-born women (n = 1474; 11.6%). Structural racism was associated with an elevated risk of PTB (RR 1.19, 95% CI 1.12, 1.26) and SGA (RR 1.19, 95% CI 1.13, 1.25) for all Black women, however, there was heterogeneity by nativity, with US-born women experiencing a higher magnitude of effect than African-born women. CONCLUSIONS: Among Black women in California, exposure to structural racism and the impacts of structural racism on the risk of PTB and SGA varied by nativity.