PURPOSE: To measure associations of area-level racial and economic residential segregation with severe maternal morbidity (SMM).

METHODS: We conducted a retrospective cohort study of births at two Philadelphia hospitals between 2018-2020 to analyze associations of segregation, quantified using the Index of Concentration at the Extremes (ICE), with SMM. We used stratified multivariable, multilevel, logistic regression models to determine whether associations of ICE with SMM varied by self-identified race or hospital catchment.

RESULTS: Of the 25,979 patients (44.1% Black, 35.8% White), 1,381 (5.3%) had SMM (Black [6.1%], White [4.4%]). SMM was higher among patients residing outside (6.3%), then inside, (5.0%) Philadelphia (P<0.001). Overall, ICE was not associated with SMM. However, ICE (higher proportion of White vs. Black households) was associated with lower odds of SMM among patients residing inside Philadelphia (aOR 0.87, 95% CI: 0.80-0.94) and higher odds outside Philadelphia (aOR 1.12, 95% CI: 0.95-1.31). Moran's I indicated spatial autocorrelation of SMM overall (P<0.001); when stratified, autocorrelation was only evident outside Philadelphia.

CONCLUSIONS: Overall, ICE was not associated with SMM. However, higher ICE was associated with lower odds of SMM among Philadelphia residents. Findings highlight the importance of hospital catchment area and referral patterns in spatial analyses of hospital datasets.

OBJECTIVE: We aimed to determine whether coronavirus-disease-2019 (COVID-19) pandemic exposure duration was associated with PTB and if the pandemic modified racial disparities.

STUDY DESIGN: We analyzed Philadelphia births and replicated in New Haven. Compared to matched months in two prior years, we analyzed overall PTB, specific PTB phenotypes, and stillbirth.

RESULTS: Overall, PTB was similar between periods with the following exceptions. Compared to pre-pandemic, early pregnancy (<14 weeks') pandemic exposure was associated with lower risk of PTB < 28 weeks' (aRR 0.60 [0.30-1.10]) and later exposure with higher risk (aRR 1.77 [0.78-3.97]) (interaction p = 0.04). PTB < 32 weeks' among White patients decreased during the pandemic, resulting in non-significant widening of the Black-White disparity from aRR 2.51 (95%CI: 1.53-4.16) to aRR 4.07 (95%CI: 1.56-12.01) (interaction P = 0.41). No findings replicated in New Haven.

CONCLUSION: We detected no overall pandemic effects on PTB, but potential indirect benefits for some patients which could widen disparities remains possible.

Infants born preterm are at risk of neonatal morbidity and mortality. Preterm birth (PTB) can be categorized as either spontaneous (sPTB) or medically indicated (mPTB), resulting from distinct pathophysiologic processes such as preterm labor or preeclampsia, respectively. A growing body of literature has demonstrated the impacts of nitrogen dioxide (NO) and benzene exposure on PTB, though few studies have investigated how these associations may differ by PTB subtype. We investigated the associations of NO and benzene exposure with sPTB and mPTB among 18,616 singleton live births at two Philadelphia hospitals between 2013 and 2017. Residential NO exposure was estimated using a land use regression model and averaged over the patient's full pregnancy. Benzene exposure was estimated at the census tract level using National Air Toxics Assessment (NATA) exposure data from 2014. We used logistic mixed-effects models to calculate odds ratios for overall PTB, sPTB, and mPTB separately, adjusting for patient- and tract-level confounders. Given the known racial segregation and PTB disparities in Philadelphia, we also examined race-stratified models. Counter to the hypothesis, neither NO nor benzene exposure differed by race, and neither were significantly associated with PTB or PTB subtypes. As such, these pollutants do not appear to explain the racial disparities in PTB in this setting.

<p><strong>BACKGROUND: </strong>Short cervix is a risk factor for preterm birth. Molecular drivers of short cervix remain elusive. Metabolites may function as mediators of pathologic processes.</p>

<p><strong>OBJECTIVES: </strong>We sought to determine if a distinct cervicovaginal metabolomic profile is associated with short cervix (&lt;25 mm) to unveil potential mechanisms by which premature cervical remodeling leads to short cervix.</p>

<p><strong>STUDY DESIGN: </strong>This was a secondary analysis of a completed prospective pregnancy cohort. Cervicovaginal fluid was obtained between 20-24 weeks' gestation. Participants selected for metabolomic profiling were frequency matched by birth outcome and cervicovaginal microbiota profile. This analysis included the 222 participants with cervical length measured. Short cervix was defined as &lt;25 mm as measured by transvaginal ultrasound. Unpaired t-tests were performed with a Bonferroni correction for multiple comparisons.</p>

<p><strong>RESULTS: </strong>There were 27 participants with short cervix and 195 with normal cervical length. Of the 637 metabolites detected, 26 differed between those with short cervix and normal cervical lengths; 22 were decreased, of which 21 belonged to the lipid metabolism pathway (all P&lt;7.85E-5). Diethanolamine, erythritol, progesterone and mannitol/sorbitol were increased in cases of short cervix. Among participants with a Lactobacillus-deficient microbiota, only diethanolamine and mannitol/sorbitol differed between short cervix (n=17) and normal cervical length (n=75), both increased.</p>

<p><strong>CONCLUSIONS: </strong>Short cervix is associated with decreased cervicovaginal lipid metabolites, particularly sphingolipids. This class of lipids stabilizes cell membranes and protects against environmental exposures. Increased diethanolamine, an immunostimulatory xenobiotic, is associated with short cervix. These observations begin to identify potential mechanisms by which modifiable environmental factors may invoke cell damage in the setting of biologic vulnerability, thus promoting premature cervical remodeling in spontaneous preterm birth.</p>